BATON ROUGE La.

A federal judge in Louisiana has overturned the conviction of a former Black Panther in the 1972 stabbing death of a prison guard.

Albert Woodfox was held in solitary confinement for over 30 years. He's one of three former Panthers known as the "Angola Three."

He and two other black prisoners at the Louisiana State Penitentiary were convicted in the killing of guard Brent Miller in April 1972.

U.S. District Judge James Brady issued a ruling late Tuesday approving a federal magistrate's recommendation that Woodfox's conviction should be overturned. The magistrate said Woodfox was denied a fair second trial because a defense lawyer failed to object to a prosecutor's testimony about a witness' credibility.

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