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Using Expert Witnesses: Product Defect Cases

A product liability case often involves some form of catastrophic personal injury. Because of this, you'll not only need experts to prove that the product was defective, but also a second set of experts to prove the damage or harm to the plaintiff.

Any product, no matter how harmless it seems, can cause injury or even death. Therefore, a wide variety of expert types may be needed. If the defective product is mechanical or physical in nature, the expert will be an engineer. However, defective products can also be medical in nature, like Dow Corning Corporation's silicone breast implants.

This article examines the basics of a product liability action and the type of experts that you may need to make your client's case.

Product Liability Basics

A products liability action assigns liability to manufacturers, suppliers, and sellers of defective goods or products for use by purchasers, users, and bystanders. Products can be defective because of a design flaw or a manufacturing flaw.

In order to prove the case, you'll need to satisfy the following elements:

  • The plaintiff was harmed by the product;
  • The product was sold, distributed or manufactured by defendant;
  • The product was unreasonably dangerous because of a design or manufacturing defect;
  • The product was used as intended and not substantially modified after purchase; and
  • There were insufficient warnings or instructions about potential hazards.

Using Expert Witnesses: Proving That the Product Caused the Harm

Most of the time it's obvious that a particular defective product caused a plaintiff's injury. In such cases, all that may be needed are medical experts to discuss the injury and its effects. However, there are cases where it may be necessary to prove that the product was in fact defective and the cause of the injury. Experts for this purpose fall into two categories: medical professionals and engineers.

Medical Experts

The type of medical provider that you may need for your case ranges from a family practitioner or general doctor to specific specialists or even a toxicologist. Certainly, a doctor will be needed to explain injuries, give a prognosis, and to review medical records. They may also be needed to demonstrate the link between any medicines, lotions, powders, and other items used on the human body and the harm that resulted. Such medical experts were necessary in the Johnson & Johnson Talcum Powder cases, for example, where the plaintiffs' ovarian cancer needed to be linked to the use of talcum powder. Other medical experts you may need include:

  • Medical doctors;
  • Nurses;
  • Toxicologists;
  • Medical Specialists; and
  • Medical billing experts.

Engineer Experts

Engineers will be able to explain why a certain component failed and why that was the cause of an accident. Many different types of engineers may be necessary, but the foundational expert for most physical accidents will be a mechanical engineer, as demonstrated in the case of Chavez v. Glock, Inc., where a mechanical engineer and firearms expert was used to test and evaluate the firearm and the holster.

For product failure cases the type of experts you will need will be engineers or industry experts, which can include:

  • Chemical engineers;
  • Electrical engineers;
  • Safety engineers;
  • Material science engineers;
  • Metallurgical engineers;
  • Biomechanical engineers;
  • Mechanical engineers; and
  • Accident reconstruction engineers.

Industry Specific Engineers

An expert with industry specific experience can be invaluable. Many product liability lawsuits involve a particular product, such as Firestone Tires; Takata airbags; or Philip Morris tobacco products. An expert who knows the industry can explain the customs and practices for that industry. The Ford Pinto exploding gas tank cases pivoted on the testimony of a former Ford Company automotive expert.

Using Expert Witnesses: Unreasonably Dangerous Products and Defects in Design or Manufacturing

It's not uncommon to have plaintiffs advance several theories of recovery for a product liability action. Therefore, experts should be prepared to satisfy all of the potential theories of product liability both for the plaintiff and the defense. These categories of product liability theory include:

Design Defects

A product's design can be considered defective if it did not perform as safely as an ordinary consumer would have expected when used as intended or in a foreseeable way. Alternatively, or in addition, a product's design can be considered defective if the risk of harm outweighs the benefit of the product.

Manufacturing Defects

A product can also be considered defective if it contained a defect caused by the manufacturing of the product when it left the defendant's possession, as can be seen in many defective airbag cases.

Failure to Warn

Finally, there may be nothing wrong with the design of the product or its manufacturing, but it can still be considered defective because the product had the potential to cause harm and the company failed to adequately warn the consumer of foreseeable harm, an argument usually seen in asbestos cases where plaintiffs allege a manufacturer's prior knowledge of specific harm and a failure to warn users lacking such knowledge.

Using Expert Witnesses: Qualifications

Product liability cases are usually won or lost based on expert testimony. So, it's important that you carefully choose your experts in order to survive evidentiary rules, such as those derived from Daubert v. Merrell Dow Pharmaceutical, Inc. and codified in the Federal Rules of Evidence Rule 702.

You can minimize the risk that your expert will be disqualified by properly vetting your expert and preparing them for their testimony. Failure to do so can have disastrous consequences, as happened in one case where the plaintiff's expert was disqualified for failing to meet the requirements of a 702 hearing.

You Will Also Need Experts for the Personal Injury Side of Your Case

Don't forget that once a product has been proven defective, there will still need to be proof of the plaintiff's injury and experts to prove damages as with any personal injury case. These experts include medical professionals, accountants, rehabilitation experts, and others to prove physical damages.

Product Defect Experts Can Make Your Case, but Having the Right Clients Comes First

Finding the right experts is just a part of a successful product liability practice. However, you also need to have an effective marketing plan to find the right clients. Let FindLaw help you develop your plan with its Legal Marketing Solutions.

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