Summers v. Tice, 33 Cal. 2d 80, 199 P.2d 1 (Cal. 1948)
Summers v. Tice is often cited as a pivotal tort law case concerning the application of alternative liability.
When two parties act negligently, and only one action causes harm to a plaintiff, can both be held liable when the plaintiff is unable to determine which party was responsible for the harm?
Under the doctrine of alternative liability, when multiple defendants act negligently but only one action causes harm, the burden of proof shifts to the defendants to demonstrate they were not the cause of the harm.
The California Supreme Court held that both Tice and Simonson were jointly liable for Summers' injury, as they were concurrently negligent and failed to absolve themselves of causation responsibility.
Summers v. Tice is a foundational case for law students studying tort law and the doctrine of alternative liability. It demonstrates how courts can adjust burdens of proof to prevent contravention of justice when traditional causation principles fall short. The case is frequently consulted in subsequent jurisprudence concerning collective or indistinct causation scenarios in negligence claims. Additionally, it serves as a precursor for other doctrines, such as market-share liability.