Products Liability Discovery

Products Liability Litigation: Discovery Relating to Other Products, Complaints, Injuries, and Subsequent Conduct

By Mark P. Robinson, Jr. and Kevin F. Calcagnie


For most attorneys representing plaintiffs in product liability actions, a common source of frustration is a defendant’s refusal to comply with discovery requests. When the plaintiff seeks information regarding other accidents, injuries, complaints or failures involving the same or similar products, whether through interrogatories, inspection demands, or depositions, manufacturers uniformly respond with boilerplate objections. Defendants will argue that such requests are overbroad in scope, and that the information sought is irrelevant and not reasonably calculated to lead to the discovery of admissible evidence.

Manufacturers will often demand constraints on such discovery and insist that inquiry must be limited to products identical to the product used by the plaintiff, and to accidents, injuries or complaints involving circumstances identical to the plaintiff’s accident. For example, in a case involving burn injuries sustained in a rearend collision, where it is alleged that a vehicle’s fuel system is defectively designed, a plaintiff will typically request documents from the auto manufacturer relating to complaints from outside sources about post-crash fires. The customary response, after a string of objections, is that the manufacturer will provide the requested documents, but only as to the same model and year, and only those which concern fires resulting from rear-end collisions. This frequently leads to a straightfaced denial of any knowledge of other complaints, and a claim that no records of any ‘relevant’ incidents exist.

Likewise, when discovery is sought concerning documentation generated in-house, such as product research and development, crash testing, design changes and design alternatives, manufacturers will insist upon similar limitations, and attempt to unreasonably restrict the scope of discovery to information about the product in question which was available prior to the manufacture of the product. If a manufacturer is successful in unreasonably restricting the scope of discovery, critical evidence may be concealed from the plaintiff, which is both relevant and admissible on the primary issues in a product liability case, including, but not limited to, notice, causation, the existence of a defect, and the feasibility of safer alternate designs.

This article will discuss some of the decisional authorities supporting broad discovery in products liability actions, and the evidentiary principles which can be utilized to defeat the disingenuous and unfounded claims of irrelevance and inadmissibility which often arise. These can be divided into five essential categories of proof: 1) Proof of defect; (2) Proof of causation; 3) Proof of notice; 4) Proof of feasibility of safer alternate designs; and 5) Proof of conscious disregard for safety.


Any manufacturer with even a rudimentary record keeping system will have documentary evidence concerning failures and malfunctions of its products. This may be in the form of direct complaints from customers to the manufacturer, or indirect reports such as warranty claims through dealers. It may also be derived from developmental testing, investigations by government agencies, and product liability lawsuits.

If this type of information is sought from a manufacturer, the instinctive reaction is to resist discovery and limit the plaintiff to identical products and factual circumstances. However, when evidence concerning other failures and other injuries is offered for the purpose of demonstrating the existence of a defective condition, a plaintiff is not limited to identical failures of identical products.

Failures in Prior Models

In Hasson v. Ford Motor Company (1982) 32 Cal.3d 388, 185 Cal.Rptr. 654, 650 P.2d 1171, the plaintiff suffered severe brain damage when the brakes failed on his 1966 Lincoln Continental, causing him to crash. At trial the plaintiff contended that the failure was due to a defect in the design of the braking system, which caused the brake fluid to heat up and vaporize.

On appeal from a verdict for the plaintiff, the manufacturer contended that the trial court had erred in admitting evidence of brake failures in 1965 models, arguing that the 1966 brake system had been modified and was substantially different. However, the California Supreme Court disagreed, holding that since there was some evidence that the changes were insignificant, failures occurring in 1965 models could be used to establish that the 1966 models were also defective:

“Ford argues that the trial court erred in admitting evidence of pre-recall brake failures in 1965 models. This contention is easily resolved. At trial, Ford contended that the 1966 brake system was substantially different because of design modification instituted pursuant to the recall campaign and maintained on 1966 models: The 1966 system’s fluid had a higher dry boiling point; Ford also installed a vented dust shield and changed the brake lining. Plaintiffs countered with expert testimony suggesting that the changes were insignificant and, in the case of the vented dust shield, completely ineffective. The trial court plainly had a reasonable basis for admitting evidence of the numerous failures occurring in 1965 models for the purpose of showing the nearly identical 1966 models to be similarly defective. Plaintiffs were not required to prove that the 1965 system was exactly the same as the 1966 system. ‘Identical conditions will rarely be found. Substantial similarity is normally sufficient.’ (Jensen v. Southern Pacific Company (1954) 129 Cal.App.2d 67, 74 [276 P.2d 703].) This determination ‘is primarily the function of the trial judge.'”

(32 Cal.3d at 403-4)

Under the rule relied upon by the court in Hasson, substantial similarity is all that is necessary, and a plaintiff is not required to demonstrate that other failures involved identical products. Where a similar product has failed for the same reason as the product in issue, the fact that it has different design features does not negate its relevance to demonstrate that a defect exists. (See also Elsworth v. Beech Aircraft Corp., infra.)

Other Lawsuits Involving Dissimilar Circumstances

In product liability discovery plaintiffs often request information relating to other lawsuits filed against the defendant manufacturer. Since some injuries caused by defective products occur without a lawsuit ever being filed and some fortunate individuals may escape injury despite product failures, discovery should seek any communication in the manufacturer’s possession concerning failures of the same product or similar products. However, when information regarding other lawsuits is requested the plaintiff should not allow the manufacturer to limit inquiry to lawsuits involving identical accidents.

For purposes of proving a defect, the requirement of substantial similarity should apply only to the cause of the failure and not to the factual circumstances under which it occurred. For example, in Perkins v. Superior Court (1981) 118 Cal.App.3d 761, 173 Cal.Rptr. 596, the plaintiff brought suit against a manufacturer and seller of an automobile battery when he was injured in an explosion of the battery while removing a stuck battery cap. Through interrogatories the plaintiff sought discovery about other lawsuits concerning personal injuries caused by battery explosions of the same make and model number.

The defendants objected on the grounds that, inter alia, the interrogatories were overbroad in that they were not limited to the circumstances of the accident-specifically, pulling a stuck battery cap. The trial court granted the plaintiff’s motion to compel further responses. However, it restricted the scope of the interrogatories to cases involving accidents where a person was pulling a stuck battery cap.

The court of appeal issued a peremptory writ of mandate requiring the trial court to vacate its orders and to issue new orders, holding that the trial court had abused its discretion by “too severely” restricting the scope of the interrogatories.

With respect to the restriction as to the type of accidents discoverable, the court held that discovery should not be limited to identical factual circumstances. The court pointed out that accidents may occur under varying circumstances yet still be caused by a common defect. Evidence of such other occurrences could therefore tend to establish a defect:

“The second vice of the imposed restrictions is that discovery is limited to injuries caused, in defendants’ opinion, by the pulling of a stuck battery cap. While defendants correctly note that explosions caused by extraneous electrical sparks or engine fires would not likely lead to admissible evidence and should therefore be excluded from the scope of discovery, it is reasonably likely that other, similar, external forces could trigger the same defect in design, materials or workmanship that is alleged have been triggered by plaintiff’s manipulation of the battery cap.

“The causal connection, if any, between external forces and the alleged battery defect is a matter for expert testimony and the trier of fact. To limit discovery to explosions occurring under exactly identical factual circumstances usurps the function of discovery by preventing independent development of information that could establish the existence of a common defect triggering explosions under varying, but not causally dissimilar, circumstances. Plaintiff should be allowed to obtain any leads that could reasonably tend to establish such a defect.”

(118 Cal.App.3d at 766)

As the court in Perkins recognized, a plaintiff need not establish substantial similarity as to accident facts. While circumstances of product failures may vary, if the failures result from a substantially similar cause, the evidence may establish the existence of a common defect.


Manufacturers frequently contend that testing performed on their products has no relevancy if the accident in question does not occur under identical circumstances. However, testing may reveal the existence of a defect irrespective of dissimilarities between testing conditions and the accident scenario. In Grimshaw v. Ford Motor Company (1981) 119 Cal.App.3d 757, 174 Cal.Rptr. 348, an individual was severely burned when the Ford Pinto in which he was riding was rear-ended and erupted into flames. The plaintiff contended that the fuel system was defectively designed in numerous respects, rendering it susceptible to fuel fires in the event of foreseeable collisions.

On appeal, Ford contended that the court had erred in admit-ting a report and a motion picture depicting a Ford crash test, on the grounds that the circumstances of the crash test were dissimilar. The crash test involved a 1971 Pinto prototype striking a fixed barrier at 21.5 miles per hour. The accident vehicle was a 1972 Ford Pinto which was struck by a Galaxy which had been travel-ing from 50 to 55 miles per hour and had braked to a speed of 28 to 37 miles per hour before impact. The court of appeal rejected Ford’s argument, noting that the crash test demonstrated both the existence of defects as well as Ford’s awareness of those defects:

“Ford urges that a report (Exhibit No. 95) and a motion picture depicting Ford’s crash test No. 1616 (Exhibit No. 22) should have been excluded because they were irrelevant and highly prejudicial to Ford in that they showed that in a 21.5 mile per hour crash of a 1971 Pinto prototype into a fixed barrier the filler neck of the fuel tank separated, allowing fuel to spill from the tank, whereas no such filler neck separation occurred in the Gray vehicle. Under the test for ascertaining relevancy of evidence to which we have previously alluded, we find no abuse of discretion in the court’s ruling. Not only did the filler neck separation show the vulnerability of the Pinto fuel system in a 21.5 mile per hour fixed barrier test, but crash test No. 1616, as Ford conceded, resulted in a puncture of the fuel tank from the exposed bolt heads on the differential housing. Thus, the exhibits showed the defect in the Pinto’s gas tank location and design, the hazard created by the protrusions on the differential housing, and, in addition, they served as evidence of Ford’s awareness of those defects.”

(119 Cal.App.3d at 791)

Destructive testing performed on products will rarely, if ever, simulate real world circumstances identical to the plaintiff’s accident. However, manufacturers who claim they have adequately tested their products cannot at the same time claim that testing which reveals potential failures and defects is irrelevant if it does not precisely mirror the incident in question. Adequate testing should encompass all reasonably foreseeable situations under which a product will be used, and if such testing shows a related defect it should be admissible or, in the very least, discoverable.

Time Restrictions and Complaints

Frequently, defendants will attempt to restrict discovery of complaints to those received in a limited time frame. In Perkins, supra, the trial court had limited discovery to only those lawsuits filed and served in the two years prior to the plaintiff’s accident. However, the appellate court concluded that this was unduly restrictive:

“The first vice is that the restriction as to filing dates prevents discovery of actions involving circumstances identical to those in the underlying action which were filed and served on or after the date of plaintiff’s alleged injury, November 17, 1977. This restriction would theoretically prevent plaintiff’s discovery of an action of identical causes and date of injury as his own, which was of necessity filed after the date of plaintiff’s injury. Such an action could well involve exploding batteries which were of the same make, model number and place of manufacture, and of similar date of manufacture, as the battery of which plaintiff complains. There is no reasonable basis for such restriction of discoverable actions. This restriction was a clear abuse of discretion, particularly in the absence of any evidentiary showing by defendants that a search for these later cases would require disproportionately additional effort and expense beyond that already expended in search for actions filed within two years prior to plaintiff’s injury.”

(118 Cal.App.3d at 755-6)

In attempting to discover evidence of other accidents and failures of a product, the plaintiff’s attorney should bear in mind that other occurrences, both prior and subsequent to the plaintiff’s injury, are relevant to show that a condition is in fact defective. (State of California Ex. Rel. Department of Transportation v. Superior Court (1980) 102 Cal.App.3d 25, 32, 162 Cal.Rptr. 78)


Aside from establishing the existence of a defect, evidence of failures in similar products is relevant as proof of the cause of a failure which resulted in the plaintiff’s injuries. Where it can be shown that other failures of like products were caused because of conditions similar to the accident in question, such evidence may support a conclusion that the failure was the result of the same cause.

Prior and Subsequent Failures Under Dissimilar Facts

In some situations, evidence of other accidents to prove causation may be admissible, irrespective of whether the accidents occurred under substantially similar circumstances, provided that the conditions which caused the failures are substantially similar. A case on point is Ault v. International Harvester (1974) 13 Cal.3d 113; 117 Cal.Rptr. 812; 528 P.2d 1148. Although Ault is primarily known for the rule permitting evidence of subsequent remedial measures in strict product liability actions, (infra), the court in Ault also held that other accidents, both prior and subsequent, may be admissible on the issue of causation.

In Ault, the plaintiff was injured when an aluminum gearbox on his Scout vehicle broke, causing him to lose control. At trial the plaintiff introduced evidence of two other accidents, one before and one subsequent to the subject accident. The plaintiff’s expert concluded that based upon the similarity in physical and mechanical properties of the gearboxes, ultimately the gearboxes failed due to the same cause.

On appeal the manufacturer contended that plaintiff had not demonstrated substantial similarity between the circumstances of plaintiff’s accident and the other two accidents. Affirming the verdict, the appellate court stated:

“Evidence of other accidents is admissible to prove a defective condition, knowledge, or the cause of an accident, provided that the circumstances of the other accidents are similar and not too remote. (Kopfinger v. Grand Central Pub. Market (1964) 60 Cal.2d 852, 861 [37 Cal.Rptr. 65, 389 P.2d 529]) Here, the expert witnesses had been retained in other litigation to analyze the properties of the gearboxes involved in the other accidents, and had reached the conclusion that they had failed because of metal fatigue. In the trial of the present case, they described the tests they performed, and testified that in their opinion the physical properties of all three gearboxes were similar and that the failure in the present case was also due to metal fatigue. The expert who testified regarding the first accident compared the damaged gearbox involved in that accident with the box in the present case, and stated that a blow to the gearbox would not have caused the failure in either accident. The other witness’ testimony consisted largely of an account of a scientific test he had performed on an aluminum 380 to determine its properties, and the conclusions he had reached from those tests.

“Thus, although the purpose of the testimony was to indicate that the failure of all three accidents occurred because of the failure of the gearbox, the focus was not on the accidents themselves but upon the inherent similarity and the physical and mechanical properties of the three gearboxes, all of which purportedly contained similar defects. Since there was no dispute that all three instruments were manufactured out of aluminum 380, we cannot conclude that the evidence was erroneously admitted.”

(13 Cal.3d at 121-2)

It should be noted that the court rejected the common defense claim that arises when a plaintiff attempts to proffer evidence of other accidents – i.e., that the defendant is in effect being asked to try other lawsuits. (13 Cal.3d at 121) The Ault decision demonstrates that this argument fails where the focus is on the physical and mechanical similarity of the components that have failed, as opposed to the accidents themselves. If the failure mode is similar, irrespective of the dissimilarity between the failures, the evidence should be admitted.


Evidence concerning other accidents and failures of other products is often used to demonstrate knowledge or notice to the manufacturer of the existence of a defect in one or more of its products. When such evidence is offered for the purpose of demonstrating notice, establishing similarity is less difficult than when attempting to prove the cause of an accident or the existence of a defective condition.

Complaints of Failures Under Dissimilar Circumstances

In Hasson, supra, the trial court admitted into evidence letters sent to Ford Motor Company describing incidents of brake failure in 1965 and 1966 Continentals. One letter advised that a toll road had been closed to Continentals as a result of reports of brake failures. Another letter complained of brake failure, and there was evidence that two Continental owners had related instances of brake failure.

On appeal, Ford argued that such evidence should have been excluded because the circumstances were not similar enough to the accident in question. The court held that the evidence was properly admitted, holding that the requirement of similarity of circumstances is relaxed when such evidence is offered to prove notice:

“The evidence was offered as proof that Ford had notice that the fluid boil problem persisted after the brake system was modified by the addition of different brake fluid and the vented dust shield. Ford argues that the trial judge abused his discretion by admitting the evidence because the circumstances surrounding the reported brake failures were not similar enough to those surrounding the failure which caused Hasson’s accident. (Citations)

“When evidence is offered to show only that defendant had notice of a dangerous condition, the requirement of similarity of circumstances is relaxed: ‘All that is required…is that the previous injury should be such as to attract the defendant’s attention to the dangerous situation…” (Laird v. T.W. Mather, Inc. (1958) 51 Cal.2d 210, 220 [331 P.2d 617])

“It does not appear that the evidence was improperly admitted; there were sufficient facts from which the jury could have justifiably inferred that these post recall failures were the result of fluid boil. All of the incidents were characterized by the sudden loss of all pedal and brake function after a period of continuous hard use. In several of the incidents, the evidence showed that full pedal returned within a brief period after total failure, a clear symptom of fluid boil. Although the trial judge might justifiably have excluded some of the evidence on the ground that its potential for prejudice outweighed its probative value (see Evidence Code Section 352), he did not abuse his discretion by admitting it.”

(32 Cal.3d at 404-5)

Accidents Involving Different Products

Evidence of other accidents may be admissible to show notice to the manufacturer even when they involve different types or models of products by the same manufacturer. Under circumstances where the same design defect is inherent in two or more products, if the plaintiff can establish that the accidents involving the other products could or should have put the manufacturer on notice of the common design flaw, it is not necessary to establish that the other incidents were in fact the result of the same cause.

For example, in Elsworth v. Beech Aircraft Corp. (1984) 37 Cal.3d 540; 208 Cal.Rptr. 874, 691 P.2d 630, a wrongful death action against an aircraft manufacturer, the plaintiffs alleged that a Beech Travel Air twin engine airplane had crashed due to a design defect. The plaintiffs contended that the crash resulted from the plane’s “undue spinning tendency” caused by the design of its wings. At trial the plaintiffs introduced over objection evidence of five (5) other accidents involving the Travel Air, and fifteen (15) accidents involving the Baron, a different type of plane manufactured by Beech.

On appeal following a verdict for the plaintiffs, Beech argued that the other accidents should have been excluded, because they were factually dissimilar and most of them involved a different airplane. The California Supreme Court held that the evidence was admissible on the issue of notice:

“Beech contends the other accidents were dissimilar to the event in the present case in a number of respects: Most of the accidents occurred in the Baron, an airplane different from the Travel Air; although they all involved the stall and spin of the aircraft, there was no evidence whether the airplanes entered the spin from a single engine stall, such as occurred in the present case; and other factors such as pilot error or overloading may have been responsible for the accidents.

“Plaintiffs introduced expert testimony that the defect in the design of the Travel Air was in its wings, which caused the aircraft to spin unduly in a single engine stall; that the Baron had the same design defect; and that this common characteristic produces identical single engine stall/spin characteristics. This evidence of the similarity in the design of the Baron and the Travel Air was sufficient to justify the court’s conclusion that evidence regarding accidents in the Baron was admissible.

“Moreover, even if the accidents did not occur in precisely the same manner as in the present case, testimony regarding the accidents that occurred prior to the crash of the Travel Air in this case was admissible to show that Beech had notice of a dangerous condition. For this purpose all that is required is that the previous injury should be such as to attract the defendant’s attention to the dangerous condition. (Citation) There can be no question that the prior accidents should have alerted Beech to the faulty spinning characteristics of the Travel Air. It was contrary to FAA regulations to spin either the Baron or the Travel Air, and Beech should therefore have been alerted to the fact that the spinning of the airplanes in the prior accidents was not intentional and may have been due to a defect in their design.”

(37 Cal.3d at 555)

Manufacturers are free to argue that failures of other products did not reveal a defect or did not actually make them aware of a problem. However, for purposes of proving notice all the plaintiff must show is constructive notice–i.e. that the information should have attracted the defendant’s attention or should have alerted the defendant to a potential defect.

Expert Testimony Re Consumer Complaints

In some situations evidence of other problems may have questionable probative value as notice, or may be excluded based on considerations of undue prejudice, confusion of issues or misleading the jury under Evidence Code Section 352. Yet even where a court has determined that the actual records of other incidents are inadmissible under Section 352, an expert may be permitted to testify as to the fact that complaints have been made, and the nature of those complaints, to provide the basis for an opinion that the manufacturer should have taken responsive action.

An example is found in West v. Johnson & Johnson Products, Inc. (1985) 174 Cal.App.3d 831; 220 Cal.Rptr. 437. In West, the plaintiff contracted toxic shock syndrome while using a tampon manufactured by the defendant, and brought an action based on strict product liability. During trial, one of the plaintiff’s experts testified about the nature of consumer complaints the defendant had received about the product. Although the trial court held under 352 that the complaints themselves would not be admitted into evidence, the expert was permitted to describe the nature of the complaints and read excerpts from pertinent ones.

The defendant contended on appeal that the admission of the testimony was prejudicial error because the verbatim reading of the complaints was unduly inflammatory. The defendant also contended that the complaints could not have alerted defendant to the hazard of TSS, which was unknown at the time. The appellate court concluded that evidence of the fact complaints had been made was properly admitted on the issue of notice, and that the testimony about the details of the complaints was necessary to show their relevance:

“Technically, the consumer complaints probably embodied a good deal of hearsay. Evidence about the complaints was admissible, if at all, only to show that the complaints had in fact been made. But in order to demonstrate the relevance of the complaints, some description of them had to be given; otherwise, the jury would have been told simply that ‘Consumer X complained about OB tampons,’ without more. Therefore the trial judge allowed the witness to describe the nature of the complaints and, as part of the description, to read excerpts from pertinent ones.

“The consumer complaints formed the basis of an expert’s opinion. Based on his review of the complaints, the expert testified that JJP should have initiated an ‘adequate appropriate testing program’, and that if testing had been done in 1977 or 1978, ‘We certainly would have seen toxic shock much earlier than we saw it.’ An expert is entitled to base his opinion on evidence which is not admissible. [Evidence Code Section 801 Subd. (b)]”

“JJP had ample opportunity to point out the dissimilarities between the complainants’ symptoms and the symptoms of TSS.”

(174 Cal.App.3d at 861)

Under the West decision, once the plaintiff has made a showing that the previous complaints should have attracted the manufactur-er’s attention, such evidence should be heard by the trier of fact. It is then up to the manufacturer to bring out dissimilarities in an attempt to show that it was not or could not have been on notice of a problem.


Evidence regarding a manufacturer’s other products may be relevant to the issue of safer alternate designs, even where it concerns later models and different products. This is one of the key issues in a design defect case. Under BAJI 9.00.5, the jury instruction which defines a design defect, the trier of fact is asked to consider several factors in determining whether the benefits of a design outweigh the risks:

“In determining whether the benefits of the design outweigh such risks you may consider, among other things, the gravity of the danger posed by the design, the likelihood that such danger would cause damage, the mechanical feasibility of a safer alternate design at the time of manufacture, the financial cost of an improved design, and the adverse consequences to the product and the consumer that would result from an alternate design.”

This instruction, which is based on Barker v. Lull Engineering Company, Inc. (1978) 20 Cal.3d 413, 143 Cal.Rptr. 225, 573 P.2d 443, specifically asks the jury to consider feasibility from both a mechanical as well as an economic standpoint. One of the best methods of demonstrating the availability, efficacy and economic consequences of a safer alternate design is to examine other products by the same manufacturer, or design changes made in later models of the same product.

Changes in Later Models

In Ault, supra, the plaintiff contended that the Scout’s gearbox broke because the aluminum 380 out of which it was made suffered from metal fatigue. The plaintiff’s experts testified that aluminum 380 was an unsuitable material, and that malleable iron would have been less likely to fail. They also testified that the defendant had substituted malleable iron for the aluminum 380 in the manufacture of the gearbox in Scout vehicles manufactured three years after the accident.

The manufacturer argued that this was evidence of a subsequent remedial measure, and therefore its admission violated Evidence Code Section 1151. The California Supreme Court held that such evidence was properly admitted and that 1151 does not apply in an action based on strict product liability:

“Section 1151 by its own terms excludes evidence of subsequent remedial or precautionary measures only when such evidence is offered to prove negligence or culpable conduct. In an action based upon strict liability against a manufacturer, negligence or culpability is not a necessary ingredient. The plaintiff may recover if he establishes that the product was defective, and he need not show that the defendants breached a duty of due care.” (13 Cal.3d at 118)

The court then analyzed the history and purpose of section 1151 and pointed out that other jurisdictions have admitted evidence of subsequent changes to show feasibility of improvement:

“On the other hand a number of more recent cases have recognized several exceptions to the rule of exclusion in negligence cases. For example, several decisions acknowledge that evidence of subsequent repairs is relevant to the issue of negligence, for if the changes occur closely in time they may well illustrate the feasibility of the improvement at the time of the accident, one of the normal elements in the negligence calculus.” (13 Cal.3d at 119)

The court concluded that the underlying policy of excluding evidence of subsequent remedial measures to avoid deterring repairs has no application in a product liability action:

“When the context is transformed from a typical negligence setting to the modern products liability field, however, the ‘public policy’ assumptions justifying this evidentiary rule are no longer valid. The contemporary corporate mass producer of goods, the normal products liability defendant, manufactures tens of thousands of units of goods; it is manifestly unrealistic to suggest that such a producer will forego making improvements in its product, and risk in enumerable additional lawsuits and the attendant adverse effect upon its public image, simply because evidence of adoption of such improvement made be admitted in an action founded on strict liability for recovery on an injury that preceded the improvement. In the products liability area, the exclusionary rule of section 1151 does not affect the primary conduct of the mass producer of goods, but serves merely as a shield against potential liability. In short, the purpose of section 1151 is not applicable to a strict liability case and hence its exclusionary rule should not be gratuitously extended to that field.”

(13 Cal.3d at 120)

Changes in Different Products

Not only did the court permit evidence of a change in later models of the same product, it also allowed evidence of a similar change to an entirely different component of an entirely different product manufactured by the defendant:

“Our conclusion that the evidence of the change to malleable iron in the manufacture of the gearbox does not violate section 1151 also answers defendant’s assertion that the court erred in admitting evidence that defendant had replaced the aluminum brake pedal on its fire engines with malleable iron.”

(13 Cal.3d at 121, footnote 5)

Proposed Improvements in Other Products

Evidence of proposed improvements can be relevant to show feasibility from an economic standpoint. Where the cost of a proposed design change is minimal or negligible, such evidence bears directly on the issues of the financial cost of an improved design and the adverse consequences to the product and the consumer that would result from an alternate design. In Grimshaw, supra, the trial court admitted a Ford engineering study regarding costs for improved fuel tanks. Ford contended that the trial court erroneously admitted the report because the study was for an entirely different vehicle to be built four years later. The appellate court found that the trial court had not erred, since there was testimony that the study could be applied equally to the Pinto:

“Ford contends admission into evidence over its objection of a report known as the ‘Chiara Memorandum’ (Plaintiff’s Exhibit No. 82) was error. The report, dated February 1971, was a Ford engineering study of the costs of a proposal for a fuel tank over the axle and a tank within a tank for a Ford-Mercury automobile. Ford argues that the study was irrelevant because it pertained to an entirely different car to be built four years later. Mr. Copp testified, however, that the information in the study could be applied equally to the Pinto. The study showed that the cost of placing the gas tank over the axle with protective shield was about $10.00 and that a tank within a tank would polyurethane foam between tanks would have cost about $5.00. When the probative value of the evidence was outweighed by the danger of undue prejudice was a matter for the trial judge.”

(119 Cal.App.3d at 791)

Because of the importance of feasibility of safer alternate designs, in preparing a discovery plan the plaintiff’s attorney should perform an informal investigation into other product lines by the same manufacturer. This will not only assist in identifying similar products and product lines with defects common to the product which injured the plaintiff, but will also identify safer alternate designs.

Later models of the same product as well as other products of the same vintage as the one in issue may incorporate design changes, improvements or ‘fixes’ which demonstrate availability and feasibility of safer alternate designs. The plaintiff’s attorney should therefore utilize experts as well as investigators to identify other relevant products and trace the manufacturer’s history of improvements made to a particular type of product.


When a plaintiff attempts to discover information relating to incidents or events subsequent to the plaintiff’s last use of a product, manufacturers will object, arguing that post accident conduct of the defendant is irrelevant since it could not have affected the plaintiff. Likewise, the manufacturer will contend that subsequent occurrences could not have provided notice to the defendant. However, independent of the relevance of such evidence to other issues, where punitive damages are sought, evidence of events occurring subsequent to the incident in question may be highly probative on the issue of conscious disregard for the safety of others.

California Civil Code Section 3294 provides that in an action for breach of an obligation arising from contract, where it is proven by clear and convincing evidence that the defendant has been guilty of oppression, fraud or malice, the plaintiff may recover damages for the sake of example and by way of punishing the defendant. Section 3294(c)(1) provides:

“‘Malice’ means conduct which is intended by the defendant to cause injury to the plaintiff or despicable conduct which is carried on by the defendant with a willful and conscious disregard of the rights or safety of others.”

Despite the fact that a defendant’s conduct may have had no possible effect on the particular plaintiff, evidence of related conduct by the defendant which amounted to a conscious disregard for the safety of others is entirely relevant to the issue of punitive damages.

Conduct Subsequent to Plaintiff’s Injury

In Hilliard v. A.H. Robins Co. (1983) 148 Cal.App.3d 374, 196 Cal.Rptr. 117, the plaintiff suffered multiple injuries as a result of a defective IUD. The trial court excluded evidence concerning the conduct of the defendant in manufacturing and marketing the product subsequent to the plaintiff’s use of the product. The appellate court held that the trial court had improperly excluded the evidence, since it was relevant to the issue of conscious disregard for the safety of others:

“We consider whether the evidence of conduct or activities of defendant Robins in manufacturing and marketing the Dalkon Shield subsequent to the IUD being placed in plaintiff, subsequent to the IUD being removed from plaintiff, and subsequent to the IUD being removed from the domestic market is admissible. We hold that it is admissible on the issues of malice and punitive damages. Proffered evidence which deals with events occurring after a plaintiff has last used the product is generally inadmissible. On the issue of malice and punitive damages, however, the plaintiff may present any evidence which would tend to prove the essential factors of the conscious disregard concept of malice. This includes evidence of subsequent activities and conduct of defendant Robins. (Blank v. Coffin (1942) 20 Cal.2d 457, 463 [126 P.2d 868]). In proving that defendant Robins acted in conscious disregard of the safety of others, plaintiff Hilliard was not limited to Robins’ conduct and activities that directly caused her injuries. The conscious disregard concept of malice does not limit an inquiry into the effect of the conduct and activities of the defendant on the plaintiff, the inquiry is directed at and is concerned with defendant’s conduct affecting the safety of others. Any evidence that directly or indirectly shows or permits an inference that defendant acted with conscious disregard of the safety or rights of others, that defendant was aware of the probable dangerous consequences of the defendant’s conduct and/or that defendant willfully and deliberately failed to avoid these consequences is relevant evidence.”

(148 Cal.App.3d at 400-1)

Injuries to Others

Hilliard also held that evidence of injuries to others was relevant to the issue of punitive damages, as well as the fact that Robins had withdrawn the Dalkon Shield from the market under pressure from the FDA:

“The trial court excluded evidence in reference to the fact that the Dalkon Shield caused septic abortions and deaths. The basis of the trial court’s ruling was that such evidence would be unduly prejudicial to defendants. (see Evidence Code Section 351) The trial court ruled that evidence that defendant Robins had taken the Dalkon Shield off the United States market on June 28, 1974, was not relevant. The trial court also excluded evidence that Robins withdrew the Dalkon Shield from the domestic market in June 1974, under some pressure from the Federal Food and Drug Administration…The excluded evidence was in each situation relevant. (Evidence Code Section 210) Evidence of death and septic abortions caused to Dalkon Shield users is relevant because it had a tendency and reason to prove that defendant was aware of the probable dangerous consequences of their plastic IUD. Evidence that defendant Robins took the Dalkon Shield off the domestic market as a result of some pressure or activity by the FDA in June 1974 is relevant if Robins was aware of the reasons of the FDA in seeking the removal of this device from the market because this evidence has a tendency and reason to prove that Robins, aware of the probable dangerous consequences of the product, willfully and deliberately failed to avoid those consequences until pressured by the FDA. Evidence of any conduct by defendant, in continuing to manufacture and market the Dalkon Shield without change, in the United States, or elsewhere, aware of the probable dangerous consequences of the IUD, is evidence having a tendency in reason to prove Robins willfully and deliberately failed to avoid those consequences.”

(148 Cal.App.3d at 398-9)

Unrelated Incidents

The Hilliard case was relied upon by the court in Barajas v. USA Petroleum Corporation (1986) 184 Cal.App.3d 974; 229 Cal.Rptr. 513, a personal injury and wrongful death action involving an explosion at a petroleum plant. In Barajas, the trial court admitted over objection evidence of failures to report fires and other fire-related incidents. Even though the incident in question involved an explosion and neither a fire nor a failure to report a fire, the court held that such evidence was relevant to show that the defendant operated its plant with a conscious disregard for the safety of others. (184 Cal.App.3d at 990)


The initial step to a successful product liability case is thorough, detailed and broad discovery calculated to uncover all relevant evidence on the issues of notice, defect and causation. However, effective follow-up is just as important. A manufacturer should not be allowed to place artificial restrictions on the scope of discovery. Whether intentional or not, boilerplate objections to legitimate discovery requests can result in concealment of significant evidence which is both relevant and admissible.

Counsel for plaintiffs should remind the defense, and the court if a motion to compel is necessary, that the rules of discovery do not require that the information sought be admissible at trial. (Pacific Telephone and Telegraph Company v. Superior Court (1970) 2 Cal.3d 161, 172; 84 Cal.Rptr. 718; 465 P.2d 854; Associated Brewers Distributing Co. v. Superior Court (1967) 65 Cal.2d 583, 587; 55 Cal.Rptr. 772; 422 P.2d 332; Greyhound Corporation v. Superior Court (1961) 56 Cal.2d 355, 391; 15 Cal.Rptr. 90; 364 P.2d 266; Bank of Orient v. Superior Court (1977) 67 Cal.App.3d 588, 599; 136 Cal.Rptr. 74)

Plaintiff’s counsel should also be well-versed in the authorities recognizing the relevance and admissibility of evidence concerning other products, complaints, injuries and subsequent conduct, which support wide latitude in product liability discovery. By resisting defense efforts to improperly restrict the boundaries of discovery and unreasonably narrow areas of inquiry, the plaintiff’s attorney will be increasing the probability of a successful outcome, while at the same time decreasing the risk of overlooking critical evidence.