O'Brian Hall is the home of the School of Law, which previously was located in downtown Buffalo. It houses classrooms, faculty offices, law student advocacy groups, and the Charles B. Sears Law Library. A distinctive architectural feature is the open-air central courtyard on the fifth floor, located atop the library. The building also houses the Francis M. Letro courtroom, a fully functional court room where actual civil and criminal trials are conducted. The courtroom also provides a forum for mock trials conducted by students in order to refine their skills in pursuit of their profession. UB Law is the only law school in the SUNY system.
John Lord O'Brian (1874-1973), a Buffalo-born 1898, graduate of the law school, served the nation in both World Wars. A Washington, D.C.-based attorney, O'Brian held various government posts and advised six presidents. He served as National Chairman of Endowment of Harvard Divinity School, U.S. Attorney for Western New York, and University Trustee from 1903 to 1929. He received the Chancellor's Award in 1940 and lived to be nearly 100.