Leiato was arrested in late April on charges of theft, criminal trespassing and criminal mischief. He also was charged in January for misdemeanor trespassing.
Ducks coach Mario Cristobal in April had said that he would take "appropriate action" once he had reviewed the case.
The 21-year-old Leiato had three sacks in the Ducks' spring game and was expected to compete for the starting position at outside linebacker. He had 14 tackles in 2017.