Det. Sgt. Chris Newcombe says police began investigating the man earlier this month when a former student of his came forward with allegations of sexual assault.
It was 3:30 a.m. Sunday when the 19-year-old woman was walking west on Oxford Street near Richmond Street and a driver tried to convince him to get into his vehicle.
Police say Farris sexually assaulted the woman, pointed a gun at her and threatened to kill her and killed her cat.
All three were released under investigation while enquiries continued, but a North Yorkshire Police spokesman confirmed on Tuesday that the investigation has now ended. She was then dropped off at the intersection of Wharncliffe Road and Oxford Street.
Evans, 68, pleaded guilty on March 21 to second-degree assault - drugging a victim and unlawful sexual contact, according to Boulder District Attorney's Office spokeswoman Catherine Olguin. The man left on foot afterwards.
Romanov is scheduled to appear in court on May 20. He has short black hair, a full beard and brown eyes.
Anyone with information about the incident is asked to call investigators with the Windsor police at 519-255-6700 ext.