Product liability refers to a claim or lawsuit against a manufacturer or seller of a product for the recovery of damages related to personal injury, death, or property damage claimed to be caused by a defective product.

The claim or lawsuit may be based on the legal theories of strict tort liability, strict products liability, negligence, misrepresentation, breach of express or implied warranty, or any other theory or combination of theories.

Product liability claims may be made against the manufacturer of component parts, an assembling manufacturer, the wholesaler, and the retailer. And product liability claims may be made by the consumer who purchased the product or by someone else who borrowed or used the product.

Product liability laws vary from state to state, and product liability claims may be based on the state’s court opinions (also known as case law or common law) or on the state’s statutes—which are usually the version of the Uniform Commercial Code (UCC) adopted by the state.

For example, under a state’s version of Article 2 of the UCC (dealing with sales of goods) there are implied warranties of merchantability and of fitness of the goods for a particular purpose included in every sale of goods. In some states these warranties may be waived by agreement, but in other states they may not be waived. See U.C.C. §2-314 and U.C.C. §2-315.

And under a strict liability theory of products liability, the amount of care or precaution taken by the manufacturer is not relevant—the manufacturer will be liable for the harm result from the defective product.

To prevail on a products liability claim, the claimant or plaintiff must prove the product:

• was defective in its design (a design defect) because there was a safer alternative design for the product;

• was defective in its manufacture (a manufacturing defect) because its production departed from the intended design, was significantly or materially different from the other products of the same design, did not work as intended, and was more dangerous to the consumer than expected; or

• was defective in its marketing (a marketing defect) because the product’s advertising and instructions for use were inadequate or failed to warn consumers of hidden (latent) dangers in the product.

In Wisconsin, product liability is governed by both state statutes and case law. The state follows the legal theories of strict liability, negligence, misrepresentation, and breach of warranty, among others, in product liability claims. Under Wisconsin law, a product may be considered defective due to design defects, manufacturing defects, or marketing defects. Design defects are present when there is a safer alternative design. Manufacturing defects occur when the product deviates from its intended design and is more dangerous than consumers expect. Marketing defects arise when there is inadequate instruction or failure to warn consumers about potential dangers. Wisconsin adheres to the Uniform Commercial Code (UCC), which includes implied warranties of merchantability and fitness for a particular purpose in the sale of goods (U.C.C. §2-314 and U.C.C. §2-315). These warranties can sometimes be waived by agreement. In strict liability cases, the manufacturer's level of care is irrelevant; they can be held liable if the product causes harm due to a defect. Claimants must prove the existence of a defect and that it caused their injury or damage to succeed in a product liability claim.