Grant B. Cooper (April 1, 1903, in New York City – May 3, 1990), was the chief defense attorney in the murder trial against Sirhan Sirhan for the assassination of Robert F. Kennedy. Sirhan's more recent counsel has accused Cooper of deliberately throwing the Sirhan case as the result of a then-pending indictment against Cooper for possessing stolen transcripts of the grand jury proceedings in the Beverly Hills Friar's Club card cheating case. Cooper, who faced the possibility of jail time, was eventually fined $1000. Cooper died in 1990 of an aortic aneurysm.
Cooper was probably most famous for his role as the lead attorney for Sirhan Sirhan, but his legal battles included many famous cases and people. His cases included defending JPL co-founder Tsien Hsue-shen against charges of being a communist and facing deportation to China and representing mob-boss Johnny Roselli in the Friar's Club case.
Cooper has also represented several Hollywood actors, including Lynne Baggett for homicide, Joan Bennett, and Shirley Temple in her divorce from John Agar.
From 1962 to 1963, Cooper was the President of the American College of Trial Lawyers.