Your attorney will want to obtain the complete history of the product, and will seek to determine the date of the original sale, identity of the dealer, distributor, subsequent purchasers, lessees and users. It is important to locate the instruction booklet, assembly booklet, warranties and all other written material that accompanied the new product at the time of the original sale and distribution. You might also be asked to help your attorney determine whether the product was modified or otherwise changed after it left the possession of the manufacturer and distributor and, if so, the identity of the persons or entities that made the modification, and the dates involved.

Experts

A successful product liability case will usually require the assistance and testimony of an expert. Typical types of experts retained in product liability cases are engineers, safety experts, and medical professionals. Finding a qualified expert early in the litigation process is usually the major factor in successfully proving a plaintiff's case.

Expert engineering testimony is often crucial to proving that a design or manufacturing defect in a product caused the plaintiff's injuries.  In addition to utilizing engineering testimony, your attorney might rely on the testimony of psychologists or experts specializing in the field of human factors. This is because sometimes, a strict engineering approach fails to consider that a product must be designed not only to work, but also so that people can safely use it. A biomechanical analysis can reveal a hidden danger for the unwary user or a practical way to prevent injuries, based on an understanding of human tendencies and behaviors.

In appropriate cases, expert testing, either destructive or nondestructive, of the product at issue may be necessary to determine whether there is evidence that the product failed or could fail in the manner alleged by the plaintiff.