The court ruled the judge should have never accepted the guilty plea from Armando Perez because, in a case of life in prison without parole, the defendant must be represented by an attorney. Perez had chosen not to have a lawyer by his side.
In October of 2010, Armando Perez waited for his estranged wife to walk by before pushing her into a City College campus bathroom, where he stabbed her to death. Prosecutors described the killing as one of the most vicious and brutal attacks they had ever seen.
Two years later, at the start of his murder trial, Perez admitted to killing Diana Gonzalez and insisted he was guilty.
"I want to let you know, I want to plead guilty to all the charges," Perez told the judge.
The San Diego County District Attorney's office is not commenting on the case.