DALLAS (AP/KXAN) – A Texas judge has vacated the conviction of a 56-year-old man after he spent 31 years in prison for aggravated sexual assault.

The Wednesday ruling by state District Judge John Creuzot means Ricky Dale Wyatt of Dallas is free on his own recognizance while the Texas Court of Criminal Appeals considers his case.

Creuzot apologized to Wyatt , who was sentenced in 1981 to 99 years in prison.

The New York-based Innocence Project asked that Wyatt’s conviction be set aside because prosecutors withheld evidence that could have helped to acquit Wyatt . The evidence contradicted the victim’s description of her attacker’s appearance.

Dallas County District Attorney Craig Watkins supported Wyatt’s release but said the case can’t yet be called an exoneration because a decision on retrying the case is still pending.

Innocence Project attorneys were instrumental in the release in October of Michael Morton of Williamson County, a man wrongfully convicted of the 1986 murder of his wife, Christine Morton. Police have charged another man, Mark Norwood , in the case after his DNA matched that found on a bloody bandana near the crime scene.

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