Duty to warn

A duty to warn is a concept that arises in the law of torts in a number of circumstances, indicating that a party will be held liable for injuries caused to another, where the party had the opportunity to warn the other of a hazard and failed to do so.

In the United States, two landmark legal cases established therapists' legal obligations to breach confidentiality if they believe a client poses a risk to himself or others. The first was Tarasoff v. Regents of the University of California (1976), where a therapist failed to inform a young woman and her parents of specific death threats made by a client. The other case was Jablonski by Pahls v. United States (1983), which further extended the responsibilities of duty to warn by including the review of previous records that might include a history of violent behavior.

The duty to warn arises in product liability cases, as manufacturers can be held liable for injuries caused by their products if the product causes an injury to a consumer and the manufacturer fails to supply adequate warnings about the risks of using the product (such as side effects from pharmacy prescriptions) or if they fail to supply adequate instructions for the proper use of the product (such as a precaution to use safety glasses when using a drill). If the manufacturer fails to supply these warnings, the law will consider the product itself to be defective.

A lawsuit by a party injured by a product, where the manufacturer failed to properly warn, is usually brought as a "negligence" action, but it could be filed as a "strict liability" claim or as a "breach of warranty of merchantability" case.

Not long after launching its Note 7 smartphone in August 2016, Samsung received many reports of burning phones. Samsung had no choice but to recall all the Galaxy Note 7s, which had cost the company around $5.3bn. Following the recall, the Federal Aviation Administration prohibited people from turning a Galaxy Note 7 on, packing it in the checked luggage, or charging it while on the plane. On October 11, 2016 Samsung stopped the production and issued a warning for people to turn the Galaxy Note 7 off and to not use it any longer. Samsung also told all of its global partners to stop selling the phone because of concerns about the product's safety. After testing 200,000 devices and 30,000 batteries, Samsung found that the overheating and the burning phones resulted from an error in the design and manufacture of the batteries on the part of its two suppliers.

An issue in product liability cases is whether the product warranted a duty to warn about known dangers. In Pavlides v. Galveston Yacht Basin (1984) the Court of Appeals for the Fifth Circuit noted "a presumption ... that, if there had been an adequate warning, the user would have read, understood, and heeded the instructions".

In the popularized 1994 Liebeck v. McDonald's Restaurants case, where the individual Liebeck sued McDonald's for damages for injuries due to spilling hot coffee on her lap, McDonald's was cited not to have properly warned consumers about the inherent danger of their coffee product, which was heated way beyond the average chain coffee's temperature. In addition, McDonald's was aware of previous injuries from hot coffee injuries and had not properly warned the consumers, which resulted in the court awarding Liebeck $640,000 in damages, which was later settled for an undisclosed amount.

Most notably, a property owner has a duty to warn persons on the property of various hazards, depending on the status of the person on the property. For example, the property owner must warn an anticipated or discovered trespasser of deadly conditions known to the property owner, but that would be hidden from the trespasser. The property owner must warn licensees of all known hazards (whether deadly or not), and must warn invitees of all dangers that the property owner can discover through a reasonable inspection of the property.