Around 4 a.m. police responded to a report of a female victim assaulted by her friend's roommate in the 800 block of Capitola Avenue.
The victim and suspect allegedly went to local bars with friends Saturday night. The female victim returned to her friend's residence that night and awoke to the suspect sexually assaulting her, police said.
Police arrested Richard Joseph Arvizu III with charges related to sexual assault.
Arvizu was booked into Santa Cruz County Jail and the incident remains under investigation.