Law clerk United States Court Appeals (District of Columbia circuit), 1966—1967, Justice Abe Fortas, United States Supreme Court, Washington, 1967—1968. Assistant United States attorney United States Attorney' General’ s Office, Southern District New York, 1968—1970. Professor law New York University, 1970—1975.
Chief Appeals Bureau. Chief assistant New York County District Attorney' General’ s Office, 1975—1980. Partner Kostelanetz & Ritholz, New York City, 1980—1986.
Corporate Counsel, 1987—1990. Partner Arnold & Porter, since 1990. Member New York City Mayor's Committee Judiciary.
Member criminal procedure law advisory committee Judicial Conference New York State.
- Perversions of Justice: The Prosecution and Acquittal of the Panther 21
- Book by Zimroth, Peter L.
Member of American Bar Association (chairman tax litigation committee, litigation section, chairman criminal procedure committee, chairman government litigation counsel), American Law Institute, Association Bar City New York (chairman criminal law committee, secretary, executive committee 1986-1990), United States Dist Court( eastern district) New York (attorney's committee grievances United States District Court (southern district) New York ), Order of Coif.