Stoops issued a statement Tuesday saying Dean's penalty is "due to a violation of team rules" but did not elaborate.
The Arizona Daily Star is reporting that Dean was arrested last Saturday and charged with one count of misconduct involving weapons. He's scheduled to appear in a Tucson court next week.
The 21-year-old Dean was expected to be one of the Wildcats' top receivers this season. He had 132 receptions for 1,407 yards and seven touchdowns in his first three years at Arizona.