LOS ANGELES - Elmer "Geronimo" Pratt, 63, a former Black Panther Party leader who spent 27 years in prison on a California murder conviction that was later overturned, died Friday in his adopted home of Tanzania.

Mr. Pratt died at his home in Imbaseni village, 15 miles from Arusha, where he had lived for at least half a decade, said a friend in Arusha, former Black Panther Pete O'Neal.

Mr. Pratt's name and his long-fought case with its political backdrop became emblematic of a tumultuous era in American history when the beret-wearing Panthers raised their fists in defiance and carried big guns, striking fear in white America.

The party, founded by Huey Newton in 1966, was targeted by then-FBI Director J. Edgar Hoover in a program that sent infiltrators into their gatherings and recruited informants. One of them, Julius Butler, was the key witness against Mr. Pratt when he was charged in 1968 with the Santa Monica tennis-court shooting of schoolteacher Caroline Olson.

Mr. Pratt, a decorated Vietnam War veteran, said he was innocent and maintained there were audiotapes that would prove he had been at a Black Panthers meeting in Oakland on the day of the killing. His lawyers later said that FBI agents and police hid and possibly destroyed wiretap evidence from the meeting, which they had under surveillance.

His 1972 conviction came during a period of turmoil marked by shootouts between police and Black Panthers, and the high-profile trial of activist professor Angela Davis, who was acquitted of murder charges.

Although the Panthers were associated with violence, they also established free breakfast programs for poor children, health clinics, and pest-control services for those who needed them.

For years, Mr. Pratt's supporters pressed for his release to no avail. But two lawyers, Stuart Hanlon and Johnnie L. Cochran, were relentless in pursuing the case. Each time they were turned down, they filed new motions. In 1997, they won. Superior Court Judge Everett Dickey granted a new trial, saying the credibility of prosecution witness Butler could have been undermined had the jury known of his relationship with law enforcement. Mr. Pratt was freed later that month.

Prosecutors announced two years later that they would abandon efforts to retry him. But they never acknowledged he was wrongly convicted.

Hanlon, the attorney who helped Mr. Pratt win his freedom, said Mr. Pratt refused to carry resentment over his treatment by the legal system. "He had no anger, he had no bitterness, he had no desire for revenge," he said.

Mr. Pratt settled a false-imprisonment and civil rights lawsuit against the FBI and the City of Los Angeles for $4.5 million in 2000.