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Case Number: D072779
Judge: Huffman, Acting P.J.
Court: California Court of Appeals Fourth Appellate District, Division One on appeal from the Superior Court, County of San Diego
Plaintiff's Attorney: John H. Gomez, Bibianne U. Fell, John Morris, and Rachel E. Moffitt
Defendant's Attorney: Kimberly S. Oberrecht, Robert A. Olson, Cynthia E. Tobisman, and Eleanor A. Ruth
Description: Plaintiff Andrew J. Pankey (Andrew) filed a products liability claim against Petco
Animal Supplies, Inc., after his son Aidan contracted a rare bacterial infection from a rat
purchased at Petco. Aidan later died as a result of complications related to his infection.
Andrew alleged, among other things, that Petco was strictly liable for injuries resulting
from the sale of the pet rat, which he argued was a product for purposes of strict products
liability. The trial court instructed the jury on negligence under ordinary negligence and
negligent failure-to-warn theories, as well as three theories of strict products liability:
(1) failure to warn, (2) manufacturing defect, and (3) design defect under a risk-benefit
test. The jury returned verdicts in favor of Petco.
On appeal, Andrew contends the trial court erred by refusing to instruct the jury on
an alternative strict liability design defect theory, the consumer expectations test. He
argues there was sufficient evidence from which the jury could have concluded the pet rat
purchased from Petco failed to perform as safely as an ordinary consumer would expect
when used in an intended or reasonably foreseeable manner.
We conclude a live pet animal sold in its unaltered state is not a product subject to
the design defect consumer expectations theory of strict products liability. Accordingly,
we affirm. Because we affirm on this basis, we need not reach a conclusion regarding the
applicability of the consumer expectations test or the prejudicial effect of its exclusion.
Were we to do so, however, we would affirm.
FACTUAL AND PROCEDURAL BACKGROUND
A. Aidan Pankey
In May 2013, 10-year-old Aidan Pankey and his grandmother visited a Petco store
to purchase a companion for Aidan's female pet rat. They selected and purchased a male
rat. Aidan kept his male rat in a vivarium at his grandmother's home, but he occasionally
handled it outside the vivarium.
Two weeks after purchasing the male rat, Aidan developed a fever, grew
increasingly lethargic, and at one point collapsed on the floor. Aidan's grandmother
called an ambulance; Aidan passed away at the hospital shortly after he arrived.
The autopsy did not disclose a cause of death or any sign of a bite or scratch.
However, analysis from Aidan's tissue samples revealed the presence of streptobacillus
moniliformis, a bacteria carried by some rats. Analysis of blood and tissue samples taken
from Aidan's rats revealed the bacteria was carried by the male rat, but not the female rat.
The parties to this suit stipulated that Aidan's death resulted from rat bite fever (RBF), an
infection caused by streptobacillus moniliformis.
B. Pretrial Proceedings
Andrew and Aidan's mother, individually and as administrators of Aidan's estate,
sued Petco and Barney's Pets, the exclusive supplier of pet rats for Petco's California
stores during the relevant time frame, alleging negligence and strict products liability.
Petco moved for summary adjudication of the strict products liability cause of
action on the basis that a pet rat is not a product. The court denied the motion,
concluding a pet rat is a product for purposes of California's strict products liability
Aidan's mother settled and dismissed her claims against the defendants.
Andrew's case proceeded to a jury trial on four theories: (1) negligence, (2) strict
liability based on a warning defect, (3) strict liability based on a manufacturing defect,
and (4) strict liability based on design defect.
1. Streptobacillus Moniliformis
Plaintiff's infectious disease expert, Dr. Joseph Vinetz, testified that 10 to 100
percent of wild rats carry the bacteria streptobacillus moniliformis. The bacteria is a
commensal organism that has adapted to live in rats, but it "doesn't have to be" present in
rats. Rats that carry streptobacillus moniliformis appear healthy and for the most part are,
but they can transmit the bacteria to one another through direct contact or their
environments, and they can transmit the bacteria to humans through bites and scratches,
or through their saliva, feces, and urine.
In humans, streptobacillus moniliformis can cause RBF, which typically manifests
itself in flu-like symptoms, a fever, a rash, and/or joint pain. Possible complications from
RBF include endocarditis (a heart valve infection), meningitis (an infection of the lining
of the brain), septic arthritis, and for 7 to 13 percent of untreated patients, death.
Sometimes, RBF resolves on its own.
Dr. Vinetz testified it is "fairly simple" to breed pathogen-free rats that do not
carry streptobacillus moniliforms, and he testified at least two laboratories had done so.1
1 The chief operations officer from Barney's testified that he purchased pathogenfree rats from one of the laboratories Dr. Vinetz cited, Harlan Laboratories, but rats from
that lab tested positive for the bacteria.
According to Dr. Vinetz, pathogen-free rats can be bred by (1) performing molecular
testing to screen out carrier rats, (2) segregating noncarrier rats in a clean facility free
from the bacteria where they are allowed to breed, (3) delivering the first-generation pups
via caesarian section (to avoid a minimal risk of transmission through the placenta),
(4) using noncarrier rats to feed new pups, and (5) permitting future generations of the
pathogen-free pups to interbreed and give birth naturally.
Randall Buck, the vice president of operations for Barney's (exclusive provider of
rats to Petco), testified that he attempted to breed pathogen-free rats. He set up a clean
facility free from the bacteria, and he purchased rats from labs that provided
documentation the rats had tested negative for the streptobacillus moniliformis. He
testified that once the rats left their original lab environments, some of them seemed to
have compromised immune systems and became ill. Although the labs provided
documentation that the rats tested negative for the streptobacillus moniliformis, he was
unsuccessful at purchasing rats that were 100 percent free from the bacteria. He testified
that the only way to be certain a rat did not carry the bacteria was to euthanize the animal
and test brain samples. He also testified that even if rats were bred in a lab to be free
from the bacteria, they might not fare well in a pet store environment because their
immune systems would be compromised. He based this belief on his own experience in
trying to do it.
2. Petco's Policies and Practices
Petco sells about 400,000 rats nationally every year. It makes periodic,
unannounced visits to the facilities of its suppliers, including Barney's, to ensure that the
animals are cared for, clean, and well-fed. Rats are not tested for streptobacillus
moniliformis as part of these audits. However, Petco requests that its suppliers provide
rats that do not carry the bacteria.
Rats can be tested for streptobacillus moniliformis through molecular testing,
called a PCR (polymerase chain reaction). Petco does not tell customers the test is
available, but if a customer asks, Petco will segregate the rat, swab its mouth, and send
the swab for testing at Petco's expense. It is not clear from the record how many
customers have requested such testing, but Petco's vice president of veterinary medicine
testified there were two instances he knew of when a customer had made such a request.
Petco will also test a rat if it bites someone. Petco tested a total of 381 rats in 2013, the
year Aidan died, and 196 of them, or 51.4 percent, tested positive for the bacteria.
If a rat bites someone and tests positive for streptobacillus moniliformis, Petco
will euthanize the rat, inform the supplier about the test result, halt further sales of rats
from the same batch (i.e., rats of the same size and gender as the carrier rat), and inform
customers who have already purchased rats from the same batch about RBF and the
positive test result.
Petco warns customers about streptobacillus moniliformis and the dangers of
bacterial transmission in three ways. First, a sign near the rat habitats entitled "Safe
Small Animal Handling" states: "All small animals can carry germs, which may infect
humans." Second, Petco posts "Care Sheets" near its rat habitats, advising customers that
"all rats are potential carriers of infectious diseases, such as Rat Bite Fever . . . ." Finally,
at the point of sale it requires that customers who intend to buy animals sign a
Companion Animal Purchase Card, which attests that the customer has reviewed caution
statements on the backside of the card. One such caution statement advises customers of
RBF, the means by which it can be transmitted to humans, and its flu-like symptoms.2
3. Consumer Expectations
Andrew elicited testimony from Aidan's grandmother and several parents of
children who contracted RBF from pet rats purchased from Petco over a period of more
than a decade. Aidan's grandmother testified she expected the pet she purchased to be
healthy and safe for her grandson. She was aware wild rats could carry disease, but she
did not expect a pet she purchased from Petco to be carrying a deadly disease. Other
parents testified they believed rats purchased from Petco would be "disease free" and that
Petco would sell rats that were "safe for children and families." Parents also testified that
they did not have any expectations about the biological makeup of the rat, that
independent research about rats explained there was a chance of getting a disease or
germs from rats, and that a few looked over the warnings, but "didn't exactly read all of
2 It reads: "Rat Bite Fever ('RBF') is a bacterial infection transmissible to people
from rats. Rats are carriers of this bacterium and show no signs of illness, however, they
can pass the bacteria on to people via bites, scratches, or accidental ingestion of
contaminated rat feces. This ingestion can take place by failing to wash your hands after
having contact with the pet or its bedding. Symptoms of infection will usually occur 2-10
days after exposure to an infected rodent and include abrupt onset of chills and fever,
vomiting, pain in the back and joints, headaches and muscle pain. A qualified physician
can make the diagnosis of RBF based on symptoms and testing for the specific strain of
bacteria causing RBF. If a rat bite occurs it would be advisable to consult a physician."
4. Jury Instructions and Special Verdict
Over Andrew's objection, the trial court declined to instruct the jury on the
consumer expectations test, a test by which a trier of fact may find a design defect if "the
circumstances of the product's failure permit an inference that the product's design
performed below the legitimate, commonly accepted minimum safety assumptions of its
ordinary consumers." (Soule v. General Motors (1994) 8 Cal.4th 548, 568-569 (Soule).)
The court opined it would be "too much" to expect a consumer to form minimum safety
assumptions about a pet rat.
The trial court instructed the jury on the risk-benefit test for purposes of design
defect theory. The risk-benefit test asks the trier of fact to determine whether the plaintiff
has proved the product's design proximately caused his injury and, if so, whether the
defendant has established that the benefits of the product's design outweigh the risk of
injury inherent in such a design. (Kim v. Toyota Motor Corp. (2018) 6 Cal.5th 21, 30
(Kim).) The court also instructed the jury on other causes of action, including negligence,
negligent failure-to-warn, strict liability failure-to-warn, and strict liability manufacturing
The jury found in favor of defendants on all causes of action. On the negligent
failure-to-warn claim, the jury determined that Petco knew or reasonably should have
known that the pet rat was dangerous or was likely to be dangerous when used or misused
in a reasonably foreseeable manner (11-1 vote), and that Petco knew or reasonably should
have known users would not realize the danger (12-0 vote), but found no liability because
Petco did not fail to adequately warn of the danger or instruct on the safe use of the pet
rat (10-2 vote). The jury also returned a defense verdict on the ordinary negligence cause
of action (12-0 vote).
The jury found in favor of defendants on each of the strict liability causes of action
as well. For the manufacturing defect claim, the jury decided the pet rat did not contain a
manufacturing defect when it left defendants' possession (11-1 vote). It also concluded
there was no strict liability for a warning defect because, although the pet rat had
potential risks that were known or knowable (11-1 vote), they did not present a
substantial danger to persons using or misusing the pet rat in an intended or reasonably
foreseeable way (10-2 vote). Finally, the jury found Petco not liable for a strict liability
design defect under the risk-benefit test because the risk of the pet rat's design did not
outweigh its design benefits (9-3 vote).
Following entry of judgment, Andrew and Barney's settled. As a result, this
appeal only concerns the judgment in favor of Petco.
Andrew challenges the judgment contending the trial court erred by refusing to
instruct the consumer expectations test as a theory on which the jury could conclude
Aidan's pet rat had a design defect. Petco offers three responses. First, it argues the
appeal is moot because Andrew did not appeal the judgment in favor of Barney's, and it
has not been vacated. Petco contends issue preclusion forecloses Andrew from
relitigating some or all issues relating to the design defect claim. Second, Petco argues a
pet rat is not a product under the strict products liability doctrine. Finally, Petco argues
the alleged design defect involves "novel and complex scientific matters" incapable of
resolution under the consumer expectations test.
We conclude Petco has not demonstrated mootness on issue preclusion grounds.
We further conclude a live pet sold in its natural form without modification does not
constitute a product under California's strict products liability design defect doctrine.
Because we conclude a pet rat is not a product for purposes of the strict products liability
design defect, we need not reach the remaining issue of the propriety of the consumer
expectations test, but were we to do so, we would conclude it was not improper for the
court to refuse that jury instruction.
Petco contends the appeal is moot because the judgment entered in Barney's favor,
which Andrew did not appeal, apparently due to the parties' postjudgment settlement,
precludes Andrew from "relitigating" the issues against Petco. It maintains that under the
doctrine of issue preclusion, the final judgment precludes Andrew "from pursuing or
continuing to pursue" a design defect theory of liability against Petco.3
We have some difficulty understanding the precise contours of Petco's issue
preclusion argument. Petco does not articulate any particular issue it believes is subject
to preclusion, instead vaguely contending the judgment in Barney's favor resolved
undefined "strict liability issues" that, according to Petco, cannot be now relitigated.
Because Petco does not identify the issue on which it bases this argument, we are inclined
to deem Petco's argument waived. (People ex rel. City of Santa Monica v. Gabriel
(2010) 186 Cal.App.4th 882, 887 ["Absent a more thorough explanation of this issue and
its purported effect, we deem the argument waived."].)
Petco may be contending that the unappealed judgment in Barney's favor
conclusively determined that Aidan's pet rat did not have a design defect; that was the
position Petco took during oral argument. But even if that were the intent, we would
reject the argument on its merits.
3 Petco sometimes indicates the judgment in Barney's favor precludes Andrew from
relitigating a strict products liability claim against Petco. However, Petco relies on the
doctrine of issue preclusion, not claim preclusion, as the basis for its mootness argument.
"It is important to distinguish these two types of preclusion because they have different
requirements." (DKN Holdings LLC v Faerber (2015) 61 Cal.4th 813, 824 (DKN).)
Because Petco provides no analysis or legal authority to support a claim preclusion
argument, we do not consider it. (Road Sprinkler Fitters Local Union No. 669 v. G&G
Fire Sprinklers, Inc. (2002) 102 Cal.App.4th 765, 772, fn. 6 [claim preclusion argument
raised for first time in appellate oral argument waived]; see City of Santa Maria v. Adam
(2012) 211 Cal.App.4th 266, 286-287 [appellant must supply cogent argument supported
by legal analysis; court may disregard arguments that fail to disclose appellant's
Issue preclusion "prohibits the relitigation of issues argued and decided in a
previous case, even if the second suit raises different causes of action." (DKN, supra, 61
Cal.4th at p. 824.) It applies "(1) after final adjudication (2) of an identical issue
(3) actually litigated and necessarily decided in the first suit and (4) asserted against one
who was a party in the first suit or one in privity with that party." (Id. at p. 825.)
Petco does not satisfy these requirements because Andrew did not litigate to
decision a design defect claim based on the consumer expectations test. The court never
offered the consumer expectations instruction; thus, the design defect issue that was
actually and necessarily decided, the risk-benefits theory, is not identical to the design
defect issue that Andrew asks to be addressed on remand. (Curtis v. State of California
ex rel. Dept. of Transportation (1982) 128 Cal.App.3d 668, 685 [contributory negligence
not actually litigated and decided in prior action because it was "specifically and
deliberately taken away from the jury"].) Accordingly, the mootness argument lacks
UNMODIFIED PET RAT IS NOT A PRODUCT
Petco next argues that the judgment should be affirmed because a live animal
cannot be a "product" for purposes of strict liability.
A. Additional Facts
Prior to trial, the defendants moved for summary adjudication on the ground that a
living animal is not a product for the purposes of strict products liability. The parties
briefed the issue, and the court denied the defendants' motion. The trial court explained:
"California courts have not addressed whether an animal is a 'product,' nor have they
adopted the Restatement (Third) for products liability, notwithstanding it has been in
existence since 1989."4
B. Products Liability: General Principles
Summary adjudication is properly granted when the moving party establishes the
right to entry of judgment as a matter of law. (Code Civ. Proc., § 437c, subd. (f).)
Whether a rat is a product for purposes of a strict products liability design defect cause of
action is a legal question, which we review de novo. (Jacks v. City of Santa Barbara
(2017) 3 Cal.5th 248, 273; Buss v. Superior Court (1997) 16 Cal.4th 35, 60; Bialo v.
Western Mutual Ins. Co. (2002) 95 Cal.App.4th 68, 76-77.) We review the decision, not
the court's rationale. (Bialo, at p. 76.)
" 'Products liability is the name currently given to the area of the law involving the
liability of those who supply goods or products for the use of others to purchasers, users,
and bystanders for losses of various kinds resulting from so-called defects in those
products.' " (Merrill v. Navegar, Inc. (2001) 26 Cal.4th 465, 478.) Liability attaches not
only to manufacturers, but also to others in the vertical chain of distribution, including
retailers, licensors, and wholesale and retail distributors. (Bay Summit Community
Assn. v. Shell Oil Co. (1996) 51 Cal.App.4th 762, 773.)
4 California courts have adopted various portions of the Restatement Third of Torts.
(See Johnson v. United States Steel Corp. (2015) 240 Cal.App.4th 22, 31-33 (Johnson)
[quoting the definition of "product"].)
"Strict liability has been invoked for three types of defects—manufacturing
defects, design defects, and 'warning defects,' i.e., inadequate warnings or failures to
warn." (Anderson v. Owens-Corning Fiberglas Corp. (1991) 53 Cal.3d 987, 995.)
"[T]he term defect as utilized in the strict liability context is neither self-defining
nor susceptible to a single definition applicable in all contexts." (Barker v. Lull
Engineering Co. (1978) 20 Cal.3d 413, 427 (Barker).) A product has a manufacturing
defect if it "differs from the manufacturer's intended result or from other ostensibly
identical units of the same product line." (Id. at p. 429.) A warning defect exists if the
manufacturer does not adequately warn the customer "of a particular risk that was known
or knowable in light of the generally recognized and prevailing scientific and medical
knowledge available at the time of the manufacture and distribution." (Anderson v.
Owens-Corning Fiberglas Corp., supra, 53 Cal.3d at p. 1002.) A product has a design
defect if it "fails to meet ordinary consumer expectations as to safety" or "the design is
not as safe as it should be." (Barker, at p. 432.) Regardless of the theory, a plaintiff must
establish "that the object or instrumentality claimed to be defective was in fact a
'product.' " (Brooks v. Eugene Burger Management Corp. (1989) 215 Cal.App.3d 1611,
1626.) We focus our analysis here on whether the rats Petco sells are products for
purposes of design defect theory.5
California law has not addressed whether an animal is a product for purposes of
strict liability. However, both the Second and Third Restatements of Torts provide some
guidance regarding what constitutes a product for strict liability claims, and whether we
apply section 402A of Restatement Second of Torts (hereafter Second Restatement) or
section 19 of the Restatement Third of Torts (hereafter Third Restatement), we reach the
same conclusion: a pet rat carrying the streptobacillus moniliformis bacteria is not
subject to a products liability design defect claim.
" ' "The Restatement . . . does not constitute a binding authority, but, considering
the circumstances under which it has been drafted, and its purposes, in the absence of a
contrary statute or decision in this state, it is entitled to great consideration as an
argumentative authority." ' " (Brady v. Calsol, Inc. (2015) 241 Cal.App.4th 1212, 1225.)
Although California has not adopted the Third Restatement, California courts have in
some circumstances cited approvingly to portions, including the definition of "product"
5 We requested supplemental briefing regarding whether the existence of
streptobacillus moniliformis in rats, to the extent it could be considered a defect, is a
manufacturing defect rather than one of design. "In general, a manufacturing or
production defect is readily identifiable because a defective product is one that differs
[(1)] from the manufacturer's intended result or [(2)] from other ostensibly identical units
of the same product . . . ." (Barker, supra, 20 Cal.3d at p. 429.) Both parties responded
that the alleged failure of the product, if it is a defect, is a design defect and not a
manufacturing defect. Without offering any opinion on the question, we accept the
parties' agreement for purposes of this appeal.
found in section 19. (Johnson, supra, 240 Cal.App.4th at p. 31; Jenkins v. T&N PLC
(1996) 45 Cal.App.4th 1224, 1229 [citing definition of "product" in draft Restatement].)
Section 19 of the Third Restatement defines a product for purposes of strict
liability as "tangible personal property distributed commercially for use or consumption,"
excluding human blood and tissue. (Rest.3d Torts, Products Liability, § 19, subds. (a),
(c).) Comment b to this section recognizes the division among courts regarding whether
living animals should be considered products for determining a commercial seller's
liability in tort and states that "when a living animal is sold commercially in a diseased
condition and causes harm to other property or to persons, the animal constitutes a
product for purposes of this Restatement." (Id., § 19, com. b.)
The definition offered in section 19 of the Third Restatement applies to all product
liability claims, but we focus on the narrower question of whether an item is a product for
the purpose of design defect claims. Comment b to the Third Restatement centers its
discussion on diseased animals, noting that diseased animals that are themselves harmed
are not eligible for recovery under the Third Restatement, while animals in a "diseased
condition" that cause harm to other property or to persons are products for which
damages are available under the Third Restatement. We focus on the issue of disease
because it is the disease from which the claim of design defect arises; absent a designed
product, there can be no design defect claim.
The dissent accuses us of failing to "address the reality" that a pet sold at a pet
store is—diseased or not—" 'tangible personal property distributed commercially for use
or consumption,' " thereby falling within the definition of "product" taken from section
19 of the Third Restatement. (Dis. opn., at pp. 5-6.) This misunderstands our point,
which is that the comment recognizes nuances involved with living animals. Comment b
to the Third Restatement does not expressly distinguish "healthy" living animals from
ones in a "diseased condition"; however, it does make clear that an animal in a "diseased
condition" is a defective product. Moreover, although it acknowledges the division
among courts regarding how to characterize living animals, comment b to the
Restatement chooses only to address animals "in a diseased condition" as products, even
though some of courts have held living animals are not defective products when the
"defect" derives from the animal's personality or dangerous propensity. (See, e.g.,
Blaha v. Stuard (S.D. S.Ct. 2002) 640 N.W.2d 85, 88-89 (Blaha) [pet dog bit child];
Kaplan v. C Lazy U Ranch (D.Colo. 1985) 615 F.Supp. 234, 237 (Kaplan) [biting and
kicking horse].) The animal's "diseased condition" is the evidence of a defective product
that brings it under Third Restatement. (See also Rest.3d Torts, supra, § 21, cmts. d-f
[discussing harms caused by defect in products as establishing eligibility for recovery
under Third Restatement].) We likewise concentrate on the role of "disease" in
determining whether a pet rat living in its natural condition, without modification, can be
a defective product.
Andrew suggests that the word "diseased" should be considered from the
perspective of the human who ultimately contracts RBF. However, "diseased" is an
adjective modifying the condition of the living animal. Neither party defines "diseased,"
but Webster's Third New International Dictionary defines it as "affected with or as if with
a disease[;] lacking health or soundness[;] sickly . . . ." (Webster's 3d New Internat. Dict.
(2002) p. 648.) Thus, under the Third Restatement, in assessing whether the rat here is a
product, we ask whether a rat carrying streptobacillus moniliformis is in a diseased
condition, i.e., affected with a disease or lacking in health or soundness. It is not, and the
parties do not disagree on this point.
Andrew's expert Dr. Vinetz explained that RBF, developed by some humans after
exposure to the streptobacillus moniliformis bacteria, is a disease of humans, not of rats.
He testified streptobacillus moniliformis bacteria is a nonessential bacteria not part of a
rat's natural flora, but instead operating as a commensal organism that resides in the
upper respiratory tract section, or the upper oropharyngeal area.6 As a commensal
organism, the bacteria adapts to the rat and the rat adapts to it. The bacteria does not
cause a disease in the rat that makes the rat sick. Thus, an animal carrying the bacteria
also does not appear sick; it has glossy fur, bright eyes, and looks alert. This testimony
makes clear that the streptobacillus moniliformis bacteria can be disease-causing in
humans, but the carrier rat is not diseased. Thus, where an animal (i.e., the rat) coexists
with an organism (streptobacillus moniliformis bacteria) and that organism causes no
harm to the animal, the animal itself is not diseased and is therefore not a product.
California has adopted outlines of the Restatement Second of Torts, section 402A.
(Cronin v. J.B.E. Olson Corp. (1972) 8 Cal.3d 121, 131.) Section 402A provides that a
6 Defense expert Dr. Sean Elliott, a pediatric infectious disease specialist, testified
that streptobacillus moniliformis is "normal flora," or part of a rat's normal intestinal
bacteria. We are not influenced by this apparently-contradictory testimony because even
considering only Dr. Vinetz's testimony, we reach the same conclusion about how to
characterize a rat carrying streptobacillus moniliformis.
party that sells a product in a defective condition is liable for the harm thereby caused to
the consumer or end user of the property as long as the seller is engaged in the business
of selling the product and the product is "without substantial change in the condition in
which it is sold." (Rest.2d Torts, supra, § 402A, subd. (1)(b).) However, its text and
comments are silent regarding the application of strict liability to live animals. (See
Rest.2d Torts, supra, § 402A.)
Courts considering strict liability claims under the Second Restatement, section
402A have reached conflicting conclusions about whether diseased animals and animals
with dangerous personalities are products. One line of cases follows a 1977 New York
opinion, Beyer v. Aquarium Supply Co. (Div. of Hartz Mountain Corp.) (N.Y. 1977) 404
N.Y.S.2d 778 (Beyer), which concluded that public policy supports holding accountable a
breeder, distributor, or vendor who places a diseased animal in the stream of commerce.
(Id. at p. 779 [diseased hamster]; see also Sease v. Taylor's Pets, Inc. (Or. App. 1985) 700
P.2d 1054 (Sease) [rabid skunk]7; Worrell v. Sachs (Conn. 1989) 563 A.2d 1387, 1387
(Worrell) [parasite-carrying puppy].)8 In Beyer, the court compared a diseased hamster
to a complex manufactured product and concluded the risk to human health from a
7 In Sease, the court reasoned that a living creature could be a product because there
was no requirement that a product be manufactured or processed, and Oregon statutes
"cover[ed] products subject both to natural change and intentional alteration," providing
an explicit defense when the seller can show the product is not in substantially the same
condition as it was when it was sold. (Sease, supra, 700 P.2d at p. 1058.)
8 The Worrell court concluded the animal's status as a product should be considered
separately from whether it had a defect and viewed a disease as a defect. (Worrell, supra,
563 A.2d at p. 1388.)
diseased animal is at least as great as that posed by a manufactured product.9 (Beyer, at
p. 779.) These cases largely concluded that a seller could control an animal's diseased
condition up to the point of sale or to address public health concerns, but they are
distinguishable from the present case because unlike the diseased animals in those cases,
rats carrying streptobacillus moniliformis are not diseased. Additionally, although
streptobacillus moniliformis may pose a risk to human health, as we explain ante, that
alone does not justify application of the design defect theory of strict liability, particularly
where—as here—other available theories of liability achieve similar goals.
Another line of cases follows Illinois decisions which have held that living
animals are not products because they are participants in "a constant interaction with the
environment around them as part of their development" and live "in a constant process of
internal development and growth." (Anderson v. Farmers Hybrid Cos. (Ill. App. 1980)
408 N.E.2d 1194, 1199 (Anderson); see also Blaha, supra, 640 N.W.2d at pp. 88-89 [pet
dog bit child]; Kaplan, supra, 615 F.Supp. at p. 237 [biting and kicking horse];
Zendejas v. Redman (S.D.Fla. June 13, 2017, No. 15-81229-CIV) 2017 U.S.Dist.Lexis
90503, *4, *19-*20 (Zendejas) [show horse that refused to jump].) These courts have
noted the animals are not "designed, assembled, fabricated . . . , produced, [or]
constructed" (Kaplan, at p. 238); they are "living, breathing, sentient creature[s] that
constantly grow, learn, experience, and change based on both external and internal
factors that often cannot be controlled by the seller . . . ." (Zendejas, at p *19.) Under
9 The Beyer court did not address the mutable nature of animals. (Beyer, supra, 404
N.Y.S.2d at p. 779.)
this line of reasoning, live animals are not products for purposes of strict liability because
there is no way to attribute their behavior solely to their status at the point of sale, as their
behavior is influenced by the surrounding environment. At the same time, these cases
recognize that the animals sold in their natural state are not "designed." (Kaplan, at
Courts have also used mutability to explain why diseased animals are not products
for purposes of strict liability. For example, in Anderson plaintiffs purchased female
breeding pigs that had a contagious and infectious disease which infected the buyers'
swine herd, requiring expensive treatment and leading to the death of several members of
the herd. (Anderson, supra, 408 N.E.2d at pp. 1195-1196.) The appellate court
concluded that to be a product, the good's nature must be fixed at the time it leaves the
manufacturer's or seller's control, and the good must reach the user without substantial
change. (Id. at p. 1199.) The court recognized that imposing strict liability helps insure
costs of injury are borne by those who market the product rather than an injured person
powerless to protect himself or herself. (Ibid.) However, it concluded that purpose is
defeated if liability is imposed on those goods whose character is "easily susceptible" to
changes beyond the control of the seller. (Ibid.) In those situations, neither party has the
power to protect against the good's changing nature; thus, it would be unfair to force the
burden on the seller over the user.
Ohio and Connecticut courts have similarly held that sick birds are not products.
In Malicki v. Koci (Ohio App. 1997) 700 N.E.2d 913 (Malicki), the court considered
whether a parakeet that transmitted psittacosis, or "parrot fever"10 to its new owners was
a product. The court held it was not, and it explained: "Imposing strict liability upon the
defendants in this case would yield the harsh result of holding them responsible as
absolute insurers of the health of a living organism whose health can be affected by many
factors totally outside the defendant's control." (Id. at p. 915.) Similarly, in Latham v.
Wal-Mart Stores, Inc. (Mo. App. 1991) 818 S.W.2d 673, a Missouri appellate court
considered whether a parrot that transmitted psittacosis was a product. The court decided
it was not: "It seems unreasonable for us to hold a seller liable for changes potentially
wrought upon a 'product' by the purchaser, while the item was completely outside the
seller's control." (Id. at p. 676.) The mutability in these cases addressed the influence of
environmental factors on the physical health of the animals rather than their personalities
or nature, but the theory remains the same: the seller cannot control outside influences or
the internal biological forces that impact the health or dangerousness of the animal.
The dissent argues that none of these authorities adopts our reasoning that only
diseased animals displaying symptoms of illness are a product. (Dis. opn., at p. 9.) This
mischaracterizes our reasoning and our conclusion. Pet rats in their natural state, even
carrying the bacteria, are neither diseased nor designed. Rats are susceptible to their
10 "Parrot fever" is caused by chlamydia psittaci. The bird in Malicki appeared
healthy upon visual inspection, and the seller's expert veterinarian testified that bird's
tissue samples showed no signs of psittacosis. (Malicki, supra, 700 N.E.2d at p. 914.)
The virologist from the Animal Disease Diagnostic Lab at Ohio State University testified
the bird was in a subclinical phase of psittacosis and had acted as a carrier of the disease.
(Ibid.) Unlike streptobacillus moniliformis, which is carried by rats as a normal
gastrointestinal, respiratory, and oral secretions and rarely affects the rat, chlamydia
psittaci can cause symptoms in the bird.
environment because nothing prevents a rat from contracting the bacteria from other rats
or the environment where the bacteria is found. To hold the seller responsible under the
design defect theory would make the seller an absolute insurer of the rat's health,
biological condition, and even behavior, even though those things are affected by factors
beyond the scope of the seller's control. (See Malicki, supra, 700 N.E.2d at p. 915.)
Additionally, even accepting that retailers and manufacturers are in the best position to
bear the cost of injuries resulting from the goods they sell (see Jimenez v. Superior Court
(2002) 29 Cal.4th 473, 477 (Jimenez)), we do not foreclose equitable cost spreading or
the apportionment of losses with our conclusion here that rats are not products for
purposes of design defect theory. Those goals can be achieved through warning and
A principal purpose behind strict products liability is to relieve injured parties of
onerous evidentiary burdens required in negligence causes of action. (Barker, supra, 20
Cal.3d at p. 431.) In design defect cases, once the plaintiff shows injury caused by a
product's design, the burden shifts to a defendant to prove the product is not defective.
(Ibid.) But this presumes there is a design to the product in the state in which it is sold,
and as we have explained pet rats living in their natural state are not designed.
We also recognize that manufacturers and retailers are generally in a strategic
position to promote the safety of the products they design. (Jimenez, supra, 29 Cal.4th at
pp. 477-478; Union Pac. Co. v. S. Cal. Edison Co. (1985) 163 Cal.App.3d 700, 709.) In
general, strict product liability promotes safer products by placing the responsibility on
the party in the best position to prevent the harm caused by their danger or defect, thereby
incentivizing proper design and quality control. (Rest.3d Torts, supra, § 2, com. a.)
However, here the offending item is a creature living in its natural state.
Finally, Andrew separately argues an animal's health is not relevant to its status as
a product for purposes of strict liability. (See Worrell, supra, 563 A.2d at p. 1387
[concluding an animal's mutability is an issue of proximate causation to be considered
separately from the animal's status as a product]; Harvey, The Applicability of Strict
Products Liability to Sales of Live Animals (1982) 67 Iowa L. Rev. 803, 815 [arguing it is
an analytical flaw to base product status on product mutability because they concern
separate elements of strict liability] (hereafter Harvey).) Under this theory, a good's
status as a product for purposes of strict liability is evaluated separately from the
requirement that it undergoes a substantial change after the seller surrenders its control.11
(Harvey, supra, 67 Iowa L. Rev. at pp. 815, 819-820.)
The difficulty with setting apart the defect from the definition of the product here
is that the policy rationale underpinning strict liability for design defect relies on the good
being defective to justify its application. For example, the cost allocation policy asks
how to appropriately allocate the cost of injury resulting from the defect. (See Barker,
supra, 20 Cal.3d at p. 431.) Here, we never reach the question of whether the bacteria is
11 One law review article promoting this approach recommends treating live animals
as products, attributing to them a presumption of mutability that results in the relevant
defect, then requiring a plaintiff to prove the animal did not experience any substantial
change after leaving the seller, i.e., the defect was present at the time of sale. (Harvey,
supra, 67 Iowa L. Rev. at p. 821.) However, this approach would be problematic in the
case before us, even if we were to consider the rat carrying the streptobacillus
moniliformis bacteria to be diseased because there is an incubation period for animals'
contraction of the bacteria; the PCR test can be negative one day and positive the next.
a defect because we have concluded it is not part of a design and does not make the rat
Still, we understand that a consumer may be unable to recognize and take
additional precautions against disease-causing bacteria an animal may carry, particularly
here, where 10 to 100 percent of pet rats carry the bacteria. The real risk is contracting
RBF without treating it. RBF is rare; there are approximately 200 documented cases in
United States history, and Petco alone sells about 400,000 rats per year. Dr. Vinetz
estimated that between zero and 10 people are admitted annually to the hospital for RBF,
but that it can sometimes resolve on its own, too.12 Those risks are better addressed by
negligence, negligent warning, and warning and manufacturing strict liability causes of
action, all of which were available to the plaintiffs and considered by the jury here.
APPLICABILITY OF CONSUMER EXPECTATIONS TEST
Andrew requested that the trial court instruct the jury on two alternative tests to
determine whether Aidan's pet rat suffered from a design defect—the risk-benefit test and
the consumer expectations test. The court provided instructions on the risk-benefit test
12 According to the Center for Disease Control, the mortality rate for untreated RBF
is 7 to 13 percent. In closing arguments, Petco's counsel argued: "Five million rats, 45
alleged claims of rat-bite fever. And the likelihood of harm occurring, again, .0009
percent . . . . [¶] . . . [¶] Are there risks of rat-bite fever? Very, very, very minimal risks.
Very, very, very minimal. The percentages are infinitesimal. They're tiny. [¶] . . . [¶]
Did the potential risk present a substantial danger to persons using or misusing the pet? I
would suggest to you that the plaintiffs have not proven there is a substantial danger that
you're going to get rat-bite fever from a rat . . . ." Even if Petco sales were attributed for
the entire universe of documented RBF cases, our calculations indicate the mortality rate
would be less than .0065 percent.
but not the consumer expectations test. Andrew contends this was error. Petco defends
the court's decision on grounds that a pet rat is inherently complex and evaluating the
circumstances of the alleged failure in this case requires scientific and medical
knowledge beyond the understanding of ordinary consumers.
Having concluded a pet rat carrying streptobacillus moniliformis is not a product
for purposes of strict liability, design defect, there is no need to consider whether the
court properly instructed the jury regarding the available tests. However, were we to
draw a conclusion on this issue, we would affirm the court's approach.
A. Consumer Expectations Test: General Principles
We review the propriety of jury instructions de novo. (Cristler v. Express
Messenger Systems, Inc. (2009) 171 Cal.App.4th 72, 82.) A plaintiff may prove the
existence of a design defect under either of two alternative tests, the consumer
expectations test (if applicable) or the risk-benefit test.13 (Barker, supra, 20 Cal.3d at
p. 432.) Under the consumer expectations test, the plaintiff may prove a design defect by
showing that the product failed to perform as safely as an ordinary consumer would
expect when used in an intended or reasonably foreseeable manner. (Ibid.) "The
rationale of the consumer expectations test is that '[t]he purposes, behaviors, and dangers
of certain products are commonly understood by those who ordinarily use them.'
[Citation.] Therefore, in some cases, ordinary knowledge of the product's characteristics
13 The Third Restatement rejects the consumer expectations test in favor of the riskbenefit test and whether there was a better alternative design available. (Webb v. Special
Electric Co., Inc. (2016) 63 Cal.4th 167, 184, fn. 8, citing Rest.3d Torts, supra, § 2,
may permit an inference that the product did not perform as safely as it should."
(Saller v. Crown Cork & Seal Co., Inc. (2010) 187 Cal.App.4th 1220, 1232 (Saller).)
The consumer expectations test considers minimum safety expectations of the product's
users, not the expectations of the general consuming public. (Demara v. The Raymond
Corp. (2017) 13 Cal.App.5th 545, 559.)
Alternatively, under the risk-benefit test, plaintiffs can prove a design defect if
they show the product's design proximately caused an injury and the defendant fails to
show the design's benefits outweigh the risk of danger inherent in the design. (Barker,
supra, 20 Cal.3d at p. 432.) When weighing the benefits and risks, a jury may consider a
nonexhaustive list of factors, including the gravity of the potential harm resulting from
the use of the product, the likelihood the harm would occur, the feasibility of an
alternative safer design at the time of manufacture, and the financial cost and
disadvantages of an alternative design. (Kim, supra, 6 Cal.5th at p. 30.)
"The tests are not mutually exclusive, and a plaintiff may proceed under either or
both." (McCabe v. American Honda Motor Co. (2002) 100 Cal.App.4th 1111, 1126
(McCabe).) However, the consumer expectations test is reserved for cases in which "the
everyday experience of the product's user permits a conclusion that the product's design
violated minimum safety assumptions," regardless of the merits of the design. (Soule,
supra, 8 Cal.4th at p. 567.) The inherent complexity of a product is not controlling on
whether the consumer expectations test applies (Saller, supra, 187 Cal.App.4th at
p. 1232), but a complex product can "cause injury in a way that does not engage its
ordinary consumers' reasonable minimum assumptions about safe performance." (Soule,
at pp. 566-567.) In such cases, the consumer expectations test does not apply. (Id. at
p. 568; see also Morson v. Superior Court (2001) 90 Cal.App.4th 775, 793-795
B. Inapplicability of Consumer Expectations Test
Petco contends the evidence adduced at trial was insufficient to warrant a jury
instruction on the consumer expectations test because the alleged failure of the product at
issue was "esoteric and inherently complex," and it could be properly understood only
with knowledge of "the biological mechanisms of pathogens, infectious diseases, and
technicalities of rat breeding for commercial and laboratory purposes." The trial court
accepted this argument, finding that RBF and the circumstances of the pet rat's alleged
failure were "too much" for an ordinary consumer to understand.
We assume for purposes of discussion that the biology of rats and the pathology of
RBF are complex topics. We recognize that the consumer expectations test can apply to
complex products, depending on the circumstances of their alleged failure. (Saller,
supra, 187 Cal.App.4th at p. 1232.) But when the ultimate issue of design defect calls for
a "careful assessment of feasibility, practicality, risk, and benefit, the case should not be
resolved simply on the basis of ordinary consumer expectations." (Soule, supra, 8
Cal.4th at p. 562.) "The critical question is whether the 'circumstances of the product's
failure permit an inference that the product's design performed below the legitimate,
commonly accepted minimum safety assumptions of its ordinary consumers.' " (McCabe,
supra, 100 Cal.App.4th at p. 1122, quoting Soule, at pp. 568-569.) However, "[s]ome
products cause injury in a way that does not engage its ordinary consumers' reasonable
minimum assumptions about safe performance." (Id. at p. 1122.) For example, when a
consumer has no idea how safe a product should be made against all foreseeable hazards,
that is, in those cases where the plaintiff's theory of defect seeks to examine obscure
behavior that falls outside the ordinary experience of the consumer, the consumer
expectation test is inapplicable, and the defect can only be proved by the risk-benefit
Because the design defect is the existence of the bacteria causing RBF, central to
the question here is whether the bacteria causing RBF can be designed out of rats, and a
consumer's ordinary experiences do not introduce it to the potential complexities of
designing a rat to be free from streptobacillus moniliformis, a bacteria which is not
readily visible in the pet rat.
Andrew's infectious disease expert Dr. Vinetz told the court RBF could not be
bred out of the rats because it was not a genetic condition. As an alternative, he testified
it would be "simple" to design a rat free from the bacteria that causes RBF, and he
described the process: The breeder would conduct a PCR to test the rats before their
breeding, only allow rats that tested negative for the bacteria to breed, deliver the pups by
cesarean section, then use rats that had tested negative to feed the new pups in a clean
facility. Dr. Vinetz testified there could be a zero percent incident rate of RBF in a
"highly controlled setting." He pointed to a research lab which provided data indicating
that over an 18-month period, it had not detected streptobacillus moniliformis in the rats
housed there. That lab bred and housed rats in its research facility; those rats never left
the facility and lived in other environments.
Defendants offered testimony regarding their unsuccessful attempts to "design"
rats without streptobacillus moniliformis through the breeding process, by purchasing rats
with documentation that they were negative for the bacteria, placing them in a separate,
clean facility, and breeding them. These efforts resulted in some offspring that tested
positive for streptobacillus moniliformis. Defendants also offered testimony that lab rats
were not always healthy and did not always fare well in the pet store environment.
Although the parties disagreed about the viability of designing rats without
streptobacillus moniliformis, both parties agreed that PCR testing could be used to assess
whether a rat carried the bacteria with 99 percent sensitivity, but the only way to be
certain a rat was free from streptobacillus moniliformis was through testing of tissue
samples after euthanizing the animal.14 Additionally, Dr. Vinetz testified that healthy
domesticated or lab rats demonstrate streptobacillus moniliformis 10 to 100 percent of the
We draw two conclusions from this evidence. First, there is no way to be certain
that any given, living rat is free from the bacteria that causes RBF. Second, it is unclear
14 Alex, the rat, was euthanized before it was tested for streptobacillus moniliformis,
and the record indicates that the initial swab was negative for the bacteria. Dr. Vinetz
testified that Alex's swab was taken from the nasopharynx instead of the oropharynx, and
he suggested the reason it came back negative was that the swab reflected the nasal
turbinates, when the bacteria is transmitted through "spit," not "snot." Subsequent tissue
testing found the bacteria in the rat's tongue, adrenal gland, several lymph nodes, and the
sciatic nerve. However, the salivary gland, soft palate, and trachea, and gastrointestinal
system were negative for streptobacillus moniliformis. Dr. Vinetz believed an oral swab
would have been positive if it had been performed.
One other witness testified the rat presumed to have caused him RBF tested
negative for RBF.
whether it is within Petco's or any supplier's control to design a rat free from
streptobacillus moniliformis. Because there is competing evidence about the
designability of a rat free from the bacteria, this is more properly a question for the jury.
However, even if the jury accepts Dr. Vinetz's testimony, this merely demonstrates there
may be a better, alternative design than the one in which rats naturally exist. This type of
alternative design is one for a jury to consider when weighing a product's benefits against
its risks to determine whether there is a design defect at all. (See Barker, supra, 20
Cal.3d at pp. 431-432.)
Ultimately, we would conclude that ordinary experience and understanding absent
a warning would not inform a consumer regarding how safely a rat should perform under
any particular set of circumstances because rats contract streptobacillus moniliformis
without notice or symptom. As a practical matter, here it is "impossible to eliminate the
balancing or weighing of competing considerations in determining whether a product is
defectively designed or not. . . ." (Barker, supra, 20 Cal.3d at p. 433.)
Additionally, as we explain post, "the issue of design defect cannot be resolved by
standardless reference to the 'expectations' of an 'ordinary consumer' " (Soule, supra, 8
Cal.4th at p. 567, citing Barker, supra, 20 Cal.3d at pp. 433-434) because the warning
here regarding the potential occurrence of RBF contributes to the " 'legitimate, commonly
accepted minimum safety assumptions' of . . . ordinary consumers." (Morson, 90
Cal.App.4th at p. 792, quoting Soule, at p. 569.)
C. Plaintiff Suffered No Prejudice
Petco maintains that even if instructions on the consumer expectations test should
have been given, the failure to do so was not prejudicial in light of the jury's conclusions
that it was not liable on either a negligence or strict liability failure-to-warn theory. We
would be inclined to agree.
1. Additional Facts
The jury was instructed on two failure-to-warn theories, strict liability and
negligence. With respect to the strict liability failure-to-warn claim, the jury answered
"yes" to the first question: "Did the pet rat have potential risks that were known or
knowable in light of the scientific and medical knowledge that was generally accepted in
the scientific community at the time of the sale?" It answered "no" to the next question:
"Did the potential risks present a substantial danger to persons using or misusing the pet
rat in an intended or reasonably foreseeable way?" With respect to strict liability, the
jury never reached the questions of whether an ordinary consumer would have recognized
potential risks and whether Petco failed to adequately warn or instruct of potential risks.
With respect to negligent failure to warn, the jury answered "yes" to the first
question: "Did Petco Animal Supplies Inc. know or should it reasonably have known that
the pet rat was dangerous or was likely to be dangerous when used or misused in a
reasonably foreseeable manner?" It answered "yes" to the second question: "Did Petco
Animal Supplies know or should it reasonably have known that users would not realize
the danger?" But it answered "no" to the third question: "Did Petco Animal Supplies
Inc. fail to adequately warn of the danger or instruct on the safe use of the pet rat?"
2. Instructional Error: General Principles
The failure to give a requested instruction in a civil suit will not result in a reversal
unless the error was prejudicial, and the appealing party must show a "reasonable
probability" that the error affected the result. (See Soule, supra, 8 Cal.4th at pp. 580-582;
People v. Watson (1956) 46 Cal.2d 818, 836.) In this context, "probability" means "a
reasonable chance, more than an abstract possibility." (Kinsman v. Unocal Corp. (2005)
37 Cal.4th 659, 682; College Hospital Inc. v. Superior Court (1994) 8 Cal.4th 704, 715.)
In assessing an instructional error's prejudicial impact, we consider the " 'natural and
probable effect on a party's ability to place his full case before the jury,' " and the
likelihood of actual prejudice, considering the state of the evidence, effect of other
instructions, effect of counsel's arguments, and any indications by that it was misled.
(Veronese v. Lucasfilm Ltd. (2012) 212 Cal.App.4th 1, 31; see Soule, at pp. 580-581.)
3. Harmless Error
The parties agree that all evidence related to the consumer expectation test was
presented to the jury. Andrew presented testimony from multiple witnesses about their
expectations when purchasing pet rats from Petco, including testimony from Aidan's
grandmother, who purchased Alex. Plaintiff's counsel asked jurors to consider this
testimony in evaluating a consumer's expectations in the context of the failure-to-warn
The dispute turns on whether it is reasonably probable, in light of the jury's
verdicts on the other causes of action, that the jury would have returned a verdict for
Andrew under the consumer expectations test. Taking into consideration the state of the
evidence, the effect of other instructions, the effect of counsel's arguments, and the
special verdicts, were we considering prejudicial effect of the exclusion of the consumer
expectations test jury instruction, we would conclude its exclusion was harmless. The
jury returned verdicts in Petco's favor on both the strict liability failure-to-warn and the
negligent failure-to-warn causes of action. Andrew contends he suffered prejudice
because the consumer expectations test is a distinct cause of action, unaffected by other
claims and their corresponding instructions. While we recognize these other causes of
action are distinguishable from the consumer expectations test, their interplay with the
ordinary consumer's expectation informs our conclusion.
The jury received instructions for the negligent and strict liability failure-to-warn
causes of action, as well as for the risk-benefit design defect claim. In general, a retailer
is strictly liable for failure to warn if the warning was feasible and its absence caused the
injury; reasonableness of the failure to warn is immaterial. (Webb v. Special Electric Co.,
Inc. (2016) 63 Cal.4th 167, 180.) A negligent failure to warn cause of action differs
because the plaintiff must prove the defendant's conduct fell below the standard of care;
thus, if a seller could reasonably decline to offer the warning, the failure to do so is not
negligent. (Id. at p. 181.)
In reaching the strict liability failure-to-warn verdict, the jury concluded the pet rat
had potential risks known and accepted in the scientific community at the time of the
sale, but those risks did not present a substantial danger to persons using the rat in an
intended or reasonably foreseeable way. The jury did not reach the question of whether
an ordinary consumer would have recognized potential risks or whether Petco failed to
adequately warn or instruct regarding those risks because it concluded they did not pose a
In reaching the negligence verdict, however, the jury did answer those questions.
It concluded that Petco knew a pet rat was likely to be dangerous, and that it should have
known its users would not realize the danger. In so holding, the jury implicitly
recognized that absent a warning, the ordinary consumer would not recognize the
potential danger wrought by a pet rat. However, the jury nonetheless concluded that
Petco did not fail to adequately warn consumers about the danger. In other words, taking
these verdicts together, the jury concluded pet rats posed a danger that the ordinary
consumer would not realize, but the danger was not substantial, and Petco supplied an
adequate warning to alert consumers to the danger. Given this conclusion, it is not
probable that the addition of the consumer expectations instruction would have resulted
in a different outcome; to hold otherwise would be to conclude it is probable the jury
would have rendered an inconsistent verdict.
Andrew explains negligent and strict liability failure-to-warn causes of action are
separate and distinct claims that do not collapse into each other merely because a plaintiff
alleges both. He then argues that just as negligent and strict liability causes of action are
different, so too are failure-to-warn and design defect causes of action. And further, the
conclusion regarding one cause of action cannot predict the jury's conclusion regarding
the other. In essence, Andrew argues that one cannot speculate as to whether adequate
warnings help frame a consumer's expectations.
Andrew cites to Saller to support this argument. There, the plaintiff filed design
defect and negligent and strict liability failure-to-warn claims against the manufacturer of
insulation containing asbestos. The trial court instructed the jury on the risk-benefit test
and a negligent failure-to-warn theory but refused the instructions for the consumer
expectations test and strict liability failure-to-warn. (Saller, supra, 187 Cal.App.4th at
p. 1230.) The jury returned defense verdicts for the claims on which it was instructed.
(Id. at pp. 1230-1231.) On appeal, the plaintiff argued the court should have instructed
on the consumer expectations test and strict liability failure-to-warn claim. (Id. at
p. 1231.) In response, the manufacturer asserted that the plaintiff did not present
evidence of what an ordinary consumer would expect, and any alleged error was harmless
due to the defense verdicts on the risk-benefit design defect and negligent failure-to-warn
claims. (Ibid.) The Court of Appeal rejected these arguments and reversed. (Id. at
pp. 1236, 1239.)
Saller is distinguishable because it answered a different question than the one
before us now. The court did not consider whether a jury's conclusion about the
adequacy of a warning would impact the verdict on a consumer expectations test in light
of the given warning; no warning was offered to consumers in Saller at all. (Saller,
supra, 187 Cal.App.4th at p. 1240.) The court concluded that the findings on negligent
failure-to-warn did not preclude a different outcome under the strict liability failure-towarn cause of action. (Ibid.)
Moreover, the issue here is not whether warning and design defect causes of action
are distinct theories;15 it is whether the inconsistent outcome that plaintiffs propose
makes it less than reasonably probable the outcome here would be different taking into
consideration the existence and adequacy of the warning that contributes to a consumer's
expectations. The parties agree that if verdicts that simultaneously conclude consumers
were adequately warned of known risks and that consumers would reasonably expect the
product to perform more safely than the warnings indicate are contradictory, they would
be fatally contradictory.16
Andrew maintains that were the instruction offered, the jury would probably have
found in his favor because the consumer expectations test does not consider the
complexity of the product, the magnitude of the danger, the feasibility of a warning, or
the reasonability of the seller. It merely considers the failure of the product without other
considerations. But this argument ignores the influence of the warning on a consumer's
15 Failure-to-warn and designed defect based on the consumer expectations test are
distinct causes of action, and plaintiffs may allege both. (Arnold v. Dow Chemical Co.
(2001) 91 Cal.App.4th 698, 717; Soule, supra, 8 Cal.4th at p. 567.)
16 Andrew explains that such an inconsistent verdict is reversible error, necessitating
a new trial. (See, e.g., City of San Diego v. D.R. Horton San Diego Holding Co., Inc.
(2005) 126 Cal.App.4th 668, 682 [inconsistent verdict rule requires a jury to resolve all
expectation.17 (See, e.g., Hansen v. Sunnyside Products, Inc. (1997) 55 Cal.App.4th
1497, 1501 [recognizing the relevance of warnings under the risk/benefit test]; see also
Rest.3d Torts, supra, § 2, com. g [explaining a consumer's expectations are influenced by
how products are portrayed and marketed].)
Andrew nonetheless contends that customers expect the rats to be healthy and
points to testimony by consumers and Petco employees about those expectations. This
testimony alone does not lead to the conclusion that it is reasonably probable the jury
would have reached a different verdict under the consumer expectations test. There was
also testimony indicating consumers had no expectations about rat biology or that they
weighed risks because they had general knowledge about the potential for disease but
purchased pet rats anyway.18
The dissent also points to testimony of consumer expectations about the safety or
health of pet rats based on factors such as Petco's slogan and pet-related custom and
17 Although no published California cases have expressly held that warning
information helps form the basis of the ordinary consumer's expectations, other
jurisdictions have drawn that conclusion. (Ford Motor Co. v. Trejo (Nev. 2017) 402 P.3d
649, 656; Knitz v. Minster Mach. Co. (Ohio Ct.App. 1987) 1987 Ohio App. Lexis 5828,
at *125; Hoffman v. Hercules Chem. Co. (N.D.Ill. 2004) 2004 U.S. Dist. Lexis 22505, at
*24).) Where there are federal, statutorily-mandated warnings, such warnings have
precluded liability under the consumer expectations test because the ordinary consumer's
expectation has been preempted by the statutory warning. (See Papike v. Tambrands Inc.
(9th Cir. 1997) 107 F.3d 737, 743 [explaining consumer not entitled to expect product to
perform more safely than government-mandated warnings and concluding warnings met
federal requirements, so design defect claim failed consumer expectations tests].)
However, we are not suggesting that a product labeled with an adequate warning will
automatically fail the consumer expectations test under California tort law, only that the
warning will inform a consumer's expectations.
18 One witness testified that he returned to Petco to get a replacement rat after the
first rat he purchased bit his son, causing RBF.
social practices as evidence that a jury may have returned a different verdict under the
consumer expectations test than it did on the risk-benefit test. (Dis. opn., at p. 15.) This
evidence points to consumer expectations without consideration of the risks arising out of
complex rat biology and the potential interaction with human beings. The dissent's
recognition that the risk of serious injury or death from a pet rat may not be consistent
with the expectations of ordinary consumers even in light of a warning that tells
consumers there is such a risk (dis. opn., at p. 17) further bolsters our conclusion that use
of standardless consumer expectations test in this case could lead a jury to completely
ignore known risks, contradicting its conclusion that Petco offered an adequate warning.
If jurors applying the consumer expectations test were to consider all the factors, as the
dissent explains they must, jurors could not simply ignore the warning, which informed
consumers that they could contract RBF from handling the pet rat. Here Andrew does
not challenge any of the jury's verdicts—not the conclusion that Petco did not act
negligently in selling the rat, nor the verdicts that Petco did not fail to adequately warn
consumers of the risk of RBF. Given consumers' knowledge of that risk, it is less than
reasonably probable the outcome here would be different under the consumer
Finally, Andrew argues that the jury's unanimous finding that consumers would
not realize the dangers inherent in Petco's product means it is reasonably probable that
the jury would have returned a verdict in Andrew's favor under a consumer expectations
theory. Courts consider the closeness of a verdict as a factor indicating prejudice.
(Griesel v. Dart Industries, Inc. (1979) 23 Cal.3d 578, 584-585; Norman v. Life Care
Centers of America (2003) 107 Cal.App.4th 1233, 1252-1253.) But here the verdict
related to the adequacy of the warning was split at 10-2, not 9-3. The verdict that was
split at 9-3 concluded the benefits of the rat's design outweighed its risks. But that does
not offer any meaningful interpretation of what the ordinary consumer's expectation was,
only that the balancing of risks and benefits was a close call. Moreover, this conclusion
is undercut by the jury's other findings, which, as we have explained, necessarily impact
what the ordinary consumer in these situations expects.
We are sympathetic to Andrew and his family for the tragic loss of Aidan.
However, because we conclude an unmodified rat is not a designed product for purposes
of design defect strict products liability, we are compelled to affirm the judgment.
Outcome: The judgment is affirmed. Parties to bear their own costs on appeal.