WEST VALLEY CITY, Utah - A repeat sex offender is off the streets thanks to some valuable evidence in a 2-year-old rape case.

West Valley City police have arrested 41-year-old David Sessions for the 2012 rape of a woman who has a mental health condition.

Officers said the woman left a voting booth and was walking through a fast food restaurant parking lot when Sessions allegedly lured her into his car and raped her.

Authorities said the woman took herself to the hospital to report the incident and have testing done.

Officials said she was not able to give an accurate description of the suspect because of her mental health condition.

Police said this case would have gone unsolved if they didn't have evidence from the rape kit.

"Through our use of DNA processing with the state lab, we were able to identify a suspect where we truly had no other information other than an unknown male from our victim," Chief Lee Russo said. "Which stresses the importance of why we need to pursue these forensic examinations and then aggressively process that information to help us get to the conclusion, getting an offender and bringing him to justice."

Chief Russo said Sessions was in jail after the alleged rape for violating parole and was nearing his release date but now will stay behind bars.

"In many circumstances, this case may not have been pressed on by an investigator but the fact that our investigator continued the investigation, was diligent about the evidence, demanded that the evidence be processed through the state crime lab, ultimately results in identifying a known sexual offender," Chief Russo said. "Here`s a individual with a history, he`s a predator in our community and now he`s off the street."

Sessions is now in the Salt Lake County Jail facing rape charges.