The 25-year-old Villanueva was released by Halton Regional Police on a promise to appear in court on July 9. The name of complainant and other details about the incident weren't available Tuesday.
His lawyer, Owen Wigderson, says Villanueva, "denies all allegations of wrongdoing and I'm very confident that he'll be exonerated.''
Villanueva averaged 11.9 points and 4.7 rebounds per game for the Pistons last season. His 2009-10 campaign is probably best remembered for when he took out his frustrations on Twitter, however, bringing a lot of unnecessary attention on himself at the end of the season.