Roy Cohn was the U.S. Senate General Counsel to the Permanent Subcommittee on Investigations (PSI) during the chairmanship of Senator Joseph McCarthy in the first half of the 1950s. Robert F. Kennedy also served on the counsel staff. He was born in New York City in 1927 to Albert Cohn, a State judge.
After attending the Columbia Law School, Cohn passed the bar exam at the age of twenty-one. He became an Assistant U.S. Attorney for the Southern district of New York state, and eventually would play a significant role in the prosecution of Ethel and Julius Rosenberg in 1951. Cohn's cross examination of Ethel Rosenberg's brother, David Greenglass, is seen as the central event in that trial, which lead to Julius Rosenberg and his wife Ethel Rosenberg's conviction and execution.
In 1952 Senator McCarthy made Roy Cohn the chief counsel to the Government Committee on Operations of the Senate. Cohn became famous for his aggressive style during the Army-McCarthy hearings. After McCarthy was censured in 1954, Cohn went into private practice. Over the next thirty years his clients included Donald Trump, Tony Salerno, and the Catholic Archdiocese of New York.
Roy Cohn died on August 2, 1986 from complications from AIDS.