Some consumer advocates believe that a products liability lawsuit is a consumer’s most effective weapon against dangerous products. While the government regulates products, regulations may not require the offending company to suffer much of a penalty. A products liability lawsuit allows the individual citizen to prosecute a case against reckless, incompetent, or negligent manufacturers. Typically, product defect cases are based on strict liability, rather than negligence. It is irrelevant whether the manufacturer or supplier exercised great care. If there is a defect in the product that causes harm, that entity will be liable for it. This means that it is not necessary to prove “fault” on the part of the defendant. To win the case, the plaintiff must prove that the product was unreasonably dangerous or defective; that injury resulted from use of the defective product; and that the injury was caused by the defect in the product. A repairer, seller, or manufacturer of a defective product is liable for injuries sustained by persons using the defective product. Liability may also extend to persons who did not purchase the product but were using the product in a foreseeable manner. Also, people injured as a result of someone else using a defective product may be able to recover if their injuries were caused by the product’s defect. All jurisdictions require a connection between the product defect and the injury. Many product liability cases turn on experts’ testimony, where both plaintiff and defendant use expert testimony to establish or deny a link between an alleged defect and an injury. Although strict liability is most common, products liability lawsuits also include negligence theories, and breach of warranty theories.