From 1990 until 1992, Tigar served as a litigation associate for the law firm Morrison & Foerster. He then served as a public defender in San Francisco from 1993 until 1994 Tigar practiced complex commercial litigation at the law firm Keker & Van Nest from 1994 until 2002. From 2002 to 2013, Tigar served as a judge on the Alameda County Superior Court. Tigar is a member of the American Law Institute, for which he served as an Adviser to the Restatement of Torts: Liability for Economic Loss and will serve in the same capacity on the forthcoming Restatement of Torts: Defamation and Privacy. Tigar has taught Pretrial Litigation at UC Berkeley's School of Law. He is a Fellow of the American Bar Foundation.
On April 2, 2015, Tigar ordered the California Department of Corrections to provide gender reassignment surgery to a transgender inmate, finding that such surgery was the only adequate medical treatment for her gender dysphoria. On October 4, 2017, in the In re Wells Fargo & Company Shareholder Derivative Litigation, Tigar allowed a shareholder lawsuit to proceed against Wells Fargo's directors, finding that it was plausible that they had "consciously disregarded their fiduciary duties despite knowledge regarding widespread illegal account-creation activities." Writing for the New York Times, financial writer Gretchen Morgenson called the ruling "unusual and welcome" and said it would "resonate among corporate directors." On November 19, 2018, Tigar issued a nationwide injunction barring the Trump administration from enforcing a rule that would deny asylum to anyone who entered the United States somewhere other than at a designated port of entry. Complaining about the ruling, President Trump characterized Tigar as an "Obama judge," prompting Chief Justice John Roberts to defend judicial independence by stating, "We do not have Obama judges or Trump judges, Bush judges or Clinton judges. What we have is an extraordinary group of dedicated judges doing their level best to do equal right to those appearing before them. That independent judiciary is something we should all be thankful for." Tigar's injunction was upheld by the Ninth Circuit Court of Appeals, and the Supreme Court allowed the injunction to remain in place pending appeal. On July 24, 2019 Tigar issued a nationwide injunction that barred the Trump administration from denying asylum to persons who crossed through but did not apply for asylum in a third country. In August, the Court of Appeals for the Ninth Circuit found the administration's asylum policy "likely violated federal regulatory law" but narrowed Tigar's injunction to apply only within the Ninth Circuit. On September 9, 2019, Tigar reinstated the nationwide scope of the injunction. The Supreme Court stayed both orders on September 11, 2019 without addressing the legality of the administration's asylum policy. On July 6, 2020, the Ninth Circuit affirmed the injunction blocking the third country asylum bar and upheld the nationwide scope of the injunction.
Community involvement
Tigar serves on the board of , a San Francisco non-profit dedicated to the support of emerging photographers and new ideas in and approaches to photography.
