Benjamin S. Kingsley

Ben is a former federal prosecutor and experienced trial lawyer whose practice focuses on government investigations, regulatory enforcement matters, and complex civil litigation. Drawing on his years of prior experience at the Department of Justice, Ben specializes in helping cutting-edge technology, fintech, life sciences, healthcare, AI, and crypto companies navigate compliance and enforcement priorities within a complex landscape shaped by federal and state regulators and other agencies, including the DOJ, SEC, CFTC, FTC, CFPB, FinCEN, IRS, and various national security agencies.

Prior to joining Fenwick, Ben worked at DOJ for almost fifteen years, including over eleven years as an Assistant U.S. Attorney in the U.S. Attorney’s Office for the Northern District of California. While at the USAO, Ben served as Chief of the Special Prosecutions Section and Chief of the Oakland Branch. In those roles, he led investigations, prosecutions, and trials of white collar, national security, cybercrime, public corruption, and civil rights cases. Ben joined the USAO as an AUSA in the Economic Crimes and Securities Fraud Section, where he investigated, prosecuted, and tried complex corporate crime and securities fraud matters. As an AUSA, Ben regularly partnered with DOJ’s National Security Division, Computer Crime and Intellectual Property Section, and Fraud Section, and with federal investigative agencies such as FBI, IRS, and Secret Service. He also worked closely with other federal regulators including the SEC, CFTC, FTC, Commerce Department’s Bureau of Industry and Security, and OFAC. During his time at the USAO, Ben was recognized with the Attorney General’s Award for Fraud Prevention for his work leading the government’s investigations into an American multinational financial services company for its opening of millions of customer accounts without authorization.

Ben began his career in the DOJ Honors Program in Washington, D.C., on the Appellate Staff of the Civil Division. In that position, he briefed and argued cases on behalf of the government across the federal circuit courts and in two state supreme courts. Working closely with Civil Division components, the Office of the Solicitor General, and other federal agencies, he was lead counsel for the United States and its agencies on cases involving constitutional law, national security law, challenges to federal regulatory programs, civil fraud, employment discrimination, and tort suits. He also served as Counsel to two Assistant Attorneys General of the Civil Division and to the Associate Attorney General, the Department’s third highest-ranking official. Ben was recognized with DOJ’s second-highest honor, the Attorney General’s Award for Distinguished Service, for his work in helping secure federal marriage equality. Ben served as DOJ's lead appellate counsel in the litigation challenging the constitutionality of the federal Defense of Marriage Act, the 1996 law that prohibited the U.S. government from recognizing same-sex marriages for purposes of federal law. Ben led the work in developing DOJ's position and briefing in the lower courts that the statute was unconstitutional, a position ultimately confirmed by the Supreme Court.

After law school, Ben clerked for the Honorable William A. Fletcher of the U.S. Court of Appeals for the Ninth Circuit.