Updated

A Texas judge has ruled that a former district attorney acted improperly when he prosecuted an innocent man who spent nearly 25 years in prison for his wife's murder.

District Judge Louis Sturns, of Fort Worth, said Friday he will issue an arrest warrant for Ken Anderson on criminal contempt and tampering charges for his handling of the case of Michael Morton.

Morton was released in 2011 after new DNA testing showed he had not killed his wife in 1985. His attorneys say Anderson hid evidence from Morton's defense that could have pointed to his innocence.

Anderson, who is now a judge, has denied any wrongdoing.