The Denver District Attorney's office says the victim had lost her friends during a St. Patrick's Day celebration and the man offered to help her find them.
Joshua Holley, 24, was found guilty of assaulting the 23-year old woman in a downtown parking garage last year on St. Patrick's Day.
Jacob Wilson, 31, was also convicted of sexual assault in the case and will be sentenced May 6.
The victim spoke after Friday's sentencing: "I have a sense of peace and closure after today. He won't even have a chance to do this again."
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