A disgraced Ohio ex-judge was on the wrong side of the bench Tuesday — and could now face life in prison for brutally stabbing his estranged wife to death.

Lance Mason, a onetime Cuyahoga County judge, pleaded guilty to aggravated murder in the Nov. 17 slaying of Aisha Fraser Mason, Cleveland.com reported.

“I wish to take responsibility for my crimes,” Mason, who has a prior conviction for beating his wife, told Judge John Haas — a retired Stark County Common Pleas Court judge brought in after Mason’s former colleagues recused themselves.

County prosecutor Michael O’Malley said the fallen judge “was on a singular mission to murder her that day.”

“There’s nothing, no reason, no act that should ever cause a human being to lash out and murder another human being,” O’Malley said in court. “I don’t care what he thinks or what he thought justified it. Nothing justifies it.”

He said he would seek the maximum sentence of life without parole.

The prosecutor said Mason was “lying in wait” outside his sister’s Shaker Heights home, where Fraser was scheduled to drop off the couple’s two children. When she arrived, an enraged Mason attacked her. Fraser could be heard screaming in the background on a recording of Mason’s sister’s 911 call.

The children could be heard screaming when Mason entered the house and said, “I’m so sorry.”

He jumped into his SUV and tried to flee but struck a local police officer who was standing outside his patrol car — sending the officer to the hospital. Mason then ran back inside the home, where he was arrested. He was indicted on murder charges shortly after the incident.

Mason, a judge since the late 1990s, had a history of domestic violence. He was forced to leave the bench in 2015 when he received a two-year sentence for punching Fraser more than a dozen times, slamming her head into the dashboard of the couple’s SUV, and chasing her out of the car in a brutal attack that left Fraser needing reconstructive surgery.

He served 10 months in prison.

His law license was indefinitely suspended in December 2017, but he continued to work as a minority business development director for the city of Cleveland — losing that job only after he was arrested for killing Fraser.

Mason said he pleaded guilty in the murder case because he did not want his daughter to have to testify if the case went to trial.