The Team, Partners and Associates

WHAT IS FORENSIC ENGINEERING?

Most manufacturing models will have a forensic component that monitors early failures to improve quality or efficiencies. Insurance companies use forensic engineers to prove liability or nonliability. Most engineering disasters (structural failures such as bridge and building collapses) are subject to forensic investigation by engineers experienced in forensic methods of investigation. Rail crashes, aviation accidents, and some automobile accidents are investigated by forensic engineers in particular where component failure is suspected. Furthermore, appliances, consumer products, medical devices, structures, industrial machinery, and even simple hand tools such as hammers or chisels can warrant investigations upon incidents causing injury or property damages. The failure of medical devices is often safety-critical to the user, so reporting failures and analysing them is particularly important. The environment of the body is complex, and implants must both survive this environment, and not leach potentially toxic impurities. Problems have been reported with breast implants, heart valves, and catheters, for example.

Failures that occur early in the life of a new product are vital information for the manufacturer to improve the product. New product development aims to eliminate defects by testing in the factory before launch, but some may occur during its early life. Testing products to simulate their behavior in the external environment is a difficult skill, and may involve accelerated life testing for example. The worst kind of defect to occur after launch is a safety-critical defect, a defect that can endanger life or limb. Their discovery usually leads to a product recall or even complete withdrawal of the product from the market. Product defects often follow the bathtub curve, with high initial failures, a lower rate during regular life, followed by another rise due to wear-out. National standards, such as those of ASTM and the British Standards Institute, and International Standards can help the designer in increasing product integrity.

Historic examples[edit]

There are many examples of forensic methods used to investigate accidents and disasters, one of the earliest in the modern period being the fall of the Dee bridge at Chester, England. It was built using cast iron girders, each of which was made of three very large castings dovetailed together. Each girder was strengthened by wrought iron bars along the length. It was finished in September 1846, and opened for local traffic after approval by the first Railway Inspector, General Charles Pasley. However, on 24 May 1847, a local train to Ruabon fell through the bridge. The accident resulted in five deaths (three passengers, the train guard, and the locomotive fireman) and nine serious injuries. The bridge had been designed by Robert Stephenson, and he was accused of negligence by a local inquest.

Although strong in compression, cast iron was known to be brittle in tension or bending. On the day of the accident, the bridge deck was covered with track ballast to prevent the oak beams supporting the track from catching fire, imposing a heavy extra load on the girders supporting the bridge and probably exacerbating the accident. Stephenson took this precaution because of a recent fire on the Great Western Railway at Uxbridge, London, where Isambard Kingdom Brunel's bridge caught fire and collapsed.

One of the first major inquiries conducted by the newly formed Railway Inspectorate was conducted by Captain Simmons of the Royal Engineers, and his report suggested that repeated flexing of the girder weakened it substantially. He examined the broken parts of the main girder, and confirmed that the girder had broken in two places, the first break occurring at the center. He tested the remaining girders by driving a locomotive across them, and found that they deflected by several inches under the moving load. He concluded that the design was flawed, and that the wrought iron trusses fixed to the girders did not reinforce the girders at all, which was a conclusion also reached by the jury at the inquest. Stephenson's design had depended on the wrought iron trusses to strengthen the final structures, but they were anchored on the cast iron girders themselves, and so deformed with any load on the bridge. Others (especially Stephenson) argued that the train had derailed and hit the girder, the impact force causing it to fracture. However, eyewitnesses maintained that the girder broke first and the fact that the locomotive remained on the track showed otherwise.

Publications[edit]

Product failures are not widely published in the academic literature or trade literature, partly because companies do not want to advertise their problems. However, it then denies others the opportunity to improve product design so as to prevent further accidents. However, a notable exception to the reluctance to publish is the journal Engineering Failure Analysis, which publishes case studies of a wide range of different products, failing under different circumstances. There are also an increasing number of textbooks becoming available.

Another notable publication, dealing with failures of buildings, bridges, and other structures, is the Journal of Performance of Constructed Facilities,^[3] which is published by the American Society of Civil Engineers, under the umbrella of its Technical Council on Forensic Engineering.^[4]

WHAT IS PRODUCT LIABILITY?

Product liability is the area of law in which manufacturers, distributors, suppliers, retailers, and others who make products available to the public are held responsible for the injuries those products cause. Although the word "product" has broad connotations, product liability as an area of law is traditionally limited to products in the form of tangible personal property.^[1]

Product liability in the United States

Theories of liability

In the United States, the claims most commonly associated with product liability are negligence, strict liability, breach of warranty, and various consumer protection claims. The majority of product liability laws are determined at the state level and vary widely from state to state.^[2] Each type of product liability claim requires different elements to be proven to present a successful claim.

Types of liability

Section 2 of the Restatement (Third) of Torts: Products Liability distinguishes between three major types of product liability claims:

• • manufacturing defect,

  • design defect,

  • a failure to warn (also known as marketing defects).

However, in most states, these are not legal claims in and of themselves, but are pleaded in terms of the theories mentioned above. For example, a plaintiff might plead negligent failure to warn or strict liability for defective design.^[3]

• • Manufacturing defects are those that occur in the manufacturing process and usually involve poor-quality materials or shoddy workmanship.

  • Design defects occur where the product design is inherently dangerous or useless (and hence defective) no matter how carefully manufactured; this may be demonstrated either by showing that the product fails to satisfy ordinary consumer expectations as to what constitutes a safe product, or that the risks of the product outweigh its benefits.^[4]

  • Failure-to-warn defects arise in products that carry inherent nonobvious dangers which could be mitigated through adequate warnings to the user, and these dangers are present regardless of how well the product is manufactured and designed for its intended purpose.

Breach of warranty

Warranties are statements by a manufacturer or seller concerning a product during a commercial transaction. Warranty claims commonly require privity between the injured party and the manufacturer or seller; in plain English, this means they must be dealing with each other directly. Breach of warranty-based product liability claims usually focus on one of three types: (1) breach of an express warranty, (2) breach of an implied warranty of merchantability, and (3) breach of an implied warranty of fitness for a particular purpose. Additionally, claims involving real estate may also take the form of an implied warranty of habitability. Express warranty claims focus on express statements by the manufacturer or the seller concerning the product (e.g., "This chainsaw is useful to cut turkeys"). The various implied warranties cover those expectations common to all products (e.g., that a tool is not unreasonably dangerous when used for its proper purpose), unless specifically disclaimed by the manufacturer or the seller.

Negligence

A basic negligence claim consists of proof of

• 1. a duty owed,

  2. a breach of that duty,

  3. the breach was the cause in fact of the plaintiff's injury (actual cause)

  4. the breach proximately caused the plaintiff's injury.

  5. and the plaintiff suffered actual quantifiable injury (damages).

As demonstrated in cases such as Winterbottom v. Wright, the scope of the duty of care was limited to those with whom one was in privity. Later cases like MacPherson v. Buick Motor Co. broadened the duty of care to all who could be foreseeably injured by one's conduct.

Over time, negligence concepts have arisen to deal with certain specific situations, including negligence per se (using a manufacturer's violation of a law or regulation, in place of proof of a duty and a breach) and res ipsa loquitur (an inference of negligence under certain conditions).

Strict liability

Main article: Strict liability

Rather than focus on the behavior of the manufacturer (as in negligence), strict liability claims focus on the product itself. Under strict liability, the manufacturer is liable if the product is defective, even if the manufacturer was not negligent in making that product defective.

The difficulty with negligence is that it still requires the plaintiff to prove that the defendant's conduct fell below the relevant standard of care. However, if an entire industry tacitly settles on a somewhat careless standard of conduct (that is, as analyzed from the perspective of a layperson), then the plaintiff may not be able to recover even though he or she is severely injured, because although the defendant's conduct caused his or her injuries, such conduct was not negligent in the legal sense (if everyone within the trade would inevitably testify that the defendant's conduct conformed to that of a reasonable tradeperson in such circumstances). As a practical matter, with the increasing complexity of products, injuries, and medical care (which made many formerly fatal injuries survivable), it is quite a difficult and expensive task to find and retain good expert witnesses who can establish the standard of care, breach, and causation.

Therefore, in the 1940s and 1950s, many American courts departed from the MacPherson standard and decided that it was too harsh to require seriously injured consumer plaintiffs to prove negligence claims against manufacturers or retailers. To avoid having to deny such plaintiffs any relief, these courts began to look for facts in their cases which they could characterize as an express or implied warranty from the manufacturer to the consumer. The res ipsa loquitur doctrine was also stretched to reduce the plaintiff's burden of proof. Over time, the resulting legal fictions became increasingly strained.

Of the various U.S. states, California was the first to throw away the fiction of a warranty and to boldly assert the doctrine of strict liability in tort for defective products, in the Supreme Court of California's decision in Greenman v. Yuba Power Products, 59 Cal. 2d 57(1963) (in which the majority opinion was authored by then-Associate Justice Roger J. Traynor). The importance of Greenman cannot be overstated: in 1996, the Association of Trial Lawyers of America (now known as the American Association of Justice) celebrated its 50th anniversary by polling lawyers and law professors on the top ten developments in tort law during the past half-century, and Greenman topped the list.^[5]

In Greenman, Traynor cited to his own earlier concurring opinion in Escola v. Coca-Cola Bottling Co., 24 Cal. 2d 453, 462 (1944) (Traynor, J., concurring). In Escola, now widely recognized as a landmark case in American law,^[6] Justice Traynor laid the foundation for Greenman with these words:

Even if there is no negligence, however, public policy demands that responsibility be fixed wherever it will most effectively reduce the hazards to life and health inherent in defective products that reach the market. It is evident that the manufacturer can anticipate some hazards and guard against the recurrence of others, as the public cannot. Those who suffer injury from defective products are unprepared to meet its consequences. The cost of an injury and the loss of time or health may be an overwhelming misfortune to the person injured, and a needless one, for the risk of injury can be insured by the manufacturer and distributed among the public as a cost of doing business. It is to the public interest to discourage the marketing of products having defects that are a menace to the public. If such products nevertheless find their way into the market it is to the public interest to place the responsibility for whatever injury they may cause upon the manufacturer, who, even if he is not negligent in the manufacture of the product, is responsible for its reaching the market. However intermittently such injuries may occur and however haphazardly they may strike, the risk of their occurrence is a constant risk and a general one. Against such a risk there should be general and constant protection and the manufacturer is best situated to afford such protection.

The year after Greenman, the Supreme Court of California proceeded to extend strict liability to all parties involved in the manufacturing, distribution, and sale of defective products (including retailers)^[7] and in 1969 made it clear that such defendants were liable not only to direct customers and users, but also to any innocent bystanders randomly injured by defective products.^[8]

Since then, many jurisdictions have been swayed by Justice Traynor's arguments on behalf of the strict liability rule in Escola, Greenman, and subsequent cases. In the 40 years after Greenman, the highest courts of nearly all U.S. states and territories followed California's example in imposing strict liability on manufacturers, distributors, and retailers for defective products. In a landmark 1986 decision, the U.S. Supreme Court embraced strict liability for defective products by adopting it as part of federal admiralty law.^[9]

Meanwhile, although the Greenman rule was transmitted to most other states via Section 402A of the Restatement of Torts, Second (published in 1964 after Greenman), the Supreme Court of California refused to adopt Section 402A's "unreasonably dangerous" limitation upon strict liability in 1972.^[10] Thus, strict liability in California is truly strict, in that the plaintiff need not show that the defect was unreasonable or dangerous. On the other hand, in California, the defendant is allowed to introduce evidence in a strict products liability action that the plaintiff contributed to his or her own injuries.^[11]

Although the Supreme Court of California has since become more conservative, it continues to endorse and expand the doctrine. In 2002 it held that strict liability for defective products even applies to makers of component products that are installed into and sold as part of real property.^[12] However, strict liability is not limitless. In 2012, the Court held that manufacturers are liable under strict liability and negligence only for defects in their products, as distinguished from other products that could potentially be used with their products.^[13]

Consumer protection

In addition to the above common law claims, many states have enacted consumer protection statutes providing for specific remedies for a variety of product defects. Statutory remedies are often provided for defects which merely render the product unusable (and hence cause economic injury) but do not cause physical injury or damage to other property; the "economic loss rule" means that strict liability is generally unavailable for products that damage only themselves. The best known examples of consumer protection laws for product defects are lemon laws, which became widespread because automobiles are often an American citizen's second-largest investment after buying a home.