Product liability law varies from state to state, and it is best to consult a board certified personal injury lawyer in your state about your claim, but the five most common ways to prove product liability are:

  1. Strict liability
  2. Negligence
  3. Warranty
  4. Misrepresentation and
  5. Intent

Strict liability, the most often pursued avenue of liability, requires the sale by a commercial supplier such as a manufacturer or retailer. Negligence is a seldom used theory because it is often easier to prove a claim for strict liability. Warranty claims include claims for expressed and implied warranties. Warranty liability may also include a claim that goods were represented as fit for a particular purpose. Warranty claims of fit for a particular purpose often cross over with claims of misrepresentation. Intentional tort claims are often hard to prove in product liability lawsuits, but these claims also include claims that the manufacturer knew with substantial certainty that an injury would occur.

Regardless of the theory of liability, the plaintiff must always be able to prove a real injury and damages. Often product liability cases are hard to prove and cost intensive to pursue. The product involved often needs to be tested by expert witnesses, who are expensive to hire. As a result, most personal injury attorneys will only pursue significant injury product liability lawsuits.