Mathew Oscar Tobriner (1904 – April 7, 1982) was an Associate Justice on the California Supreme Court from July 1962–January 1982. An appointee of Democratic Governor Pat Brown, he had worked as a labor lawyer until 1959, when Brown appointed him to the California Court of Appeal. After three years on the Court of Appeal, Tobriner was appointed by Brown to the Supreme Court. As one of the three members on the California Commission on Judicial Appointments, Tobriner cast the deciding vote in approving the nomination of Rose Bird as the first female Chief Justice on the California Supreme Court.
Tobriner was admitted before the California Bar in April 1928.
Tobriner wrote the 1974 decision of Green v. Superior Court, 517 P.2d 1168, that established the doctrine of implied warranty of habitability in residential leases in California, which requires landlords to maintain leased dwellings in a habitable condition.
Tobriner wrote the 1976 decision of Tarasoff v. Regents of the University of California, 17 Cal. 3d 425, 551 P.2d 334, 131 Cal. Rptr. 14 (Cal. 1976), the ruling that held that mental health professionals have a duty to protect individuals who are being threatened with bodily harm by a patient. He famously wrote, "...the confidential character of patient-psychotherapist communications must yield to the extent that disclosure is essential to avert danger to others. The protective privilege ends where the public peril begins..."
Tobriner also wrote the majority opinion in the landmark case of Marvin v. Marvin, 557 P.2d 106 (1976), which held that implied contracts may be found in non-marital relationships. In other words, if a couple lives together for a substantial period of time, one of the parties may be required to make payments to the other upon the dissolution of the relationship—commonly called "palimony."
Tobriner also wrote the majority opinion in People v. Woody, 394 P.2d 813 (Cal. 1964), overturning a conviction for peyote use by a Native American Church member on First Amendment grounds. Weighing the asserted compelling state interest in controlling drug abuse with the Free Exercise Clause, he found that the balance favored constitutional protection of the peyote use and practice, stating: