By CBS3 Staff

CHESTER, Pa. (CBS) — A Pennsylvania man is free after a federal court threw out his 1984 murder conviction. Willie Stokes walked out of the state correctional institution in Chester, Delaware County Tuesday afternoon.

Stokes was 37 years into a life sentence until Philadelphia District Attorney Larry Krasner’s office investigated and found that Stokes did not get due process.

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Last month, a federal court found that a key witness lied.

An attorney for Stokes said Philadelphia police offered the witness sex and drugs in exchange for false testimony.

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Stokes spoke briefly outside the prison.

“He’s only known for a half hour he was going to be released, this isn’t something that we expected,” Attorney Michael Diamondstein said.

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An attorney for Stokes said the case is an example of years of injustice against Philadelphians.