MINNEAPOLIS (WCCO) — Forensic test results gave powerful DNA evidence that Kenneth Clark is guilty of committing sexual assault in 2012, the St. Louis County Attorney’s Office said.

The office said Clark was charged in 2012 after evidence indicated he forced a woman into sexual conduct in his cab that November. Although police promptly responded, the office says miscommunication between police and the Bureau of Criminal Apprehension lab caused a delay in the investigation.

The DNA test kits used in this case are part of the Sexual Assault Kit Initiative grants introduced in 2016.

The victim is a grandmother who was contacted in 2016 by an investigator with the initiative, the office says. She wanted to proceed with the investigation and on Thursday June 20, Clark was found guilty based on the “newly discovered powerful DNA evidence,” the office said.

Clark faces a sentencing guideline of 12 years in prison, but the date is yet to be determined.