A former Flint police chief is facing criminal charges for his role in the wrongful murder conviction of a Detroit teen in 2008.

According to the Wayne County Prosecutor’s Office, a warrant is currently under review for ex-police chief James Tolbert, whose sworn testimony led to the wrongful conviction and imprisonment of then 14-year-old Davontae Sanford. Sanford was charged with the murders of four people at a drug house on Runyon Street, located on the east side of Detroit.

A hand-drawn diagram of the murder scene was used as a key piece of evidence in the Sanford case — a diagram Tolbert initially claimed was drawn by the Detroit teen. However, prosecutors say a re-investigation into Sanford’s case revealed that the ex-deputy chief had contradicted his sworn testimony.

The Guardian reports that in 2010, Tolbert testified at a court hearing that Sanford sketched a diagram of the crime scene and house. Yet, during an interview with state police last September, Tolbert admitted that he had actually drawn the sketch of the house.

“Deputy Chief Tolbert, at the time with the Detroit Police Department, responded to questions that undermined his prior testimony under oath (that Mr. Sanford created a sketch from a blank piece of paper),” Wayne County Prosecutor Kym Worthy said Thursday. “It called into question the building blocks of our case.”

According to Detroit Fox 2 News legal analyst Charlie Langton, the ex-police chief now faces life behind bars if he’s convicted of perjury.

“Perjury is lying, and when you lie under oath in a court case when your testimony could send someone in prison for life, that’s really bad,” Langton told the news station. “And the penalty for lying in that kind of case is life for you, for lying.”

The realization that Tolbert perjured himself comes shortly after the ex-police chief was forced to resign for his involvement in the Flint water crisis, ABC News reports.

It’s Tolbert’s contradictory testimony that ultimately led to the Detroit teen’s release from prison. Just last week, Sanford, now 23, walked out of prison a free man after Judge Brian Sullivan chose to vacate his conviction, according to Atlanta Black Star. Sanford spent nearly nine years behind bars for a crime he didn’t commit, even after the real perpetrator came forward and confessed to the Runyon Street murders.

According to The Guardian, Worthy strongly defended how her office handled the Sanford case at a press conference Thursday.

“This was not the Wayne County prosecutor’s office running rogue and trying to do something illegal to Mr. Sanford,” Worthy said.

Sanford’s appellate attorneys failed to pursue claims earlier that might have reversed his conviction sooner, she alleged, particularly on claims that the Detroit teenager falsely confessed.

“I don’t know what we could’ve done differently as this case went through time, I really don’t,” she continued. “I can’t be a Monday morning quarterback.”

Now that he’s free, Sanford said he’s not bitter and just wants to move forward.

“I’m not about to play the blame game with nobody,” Sanford explained. “It’s over, I’m out. Like, that’s all I really wanted was my freedom; from this day forward I’m just trying to move forward and put this behind me.