The answer to this question depends on what she has been arrested for and what his involvement has been.
At a minimum you could construct a counseling statement for the Soldier and inform him that you are recommending to the commander that certain on-post privileges be removed. In some cases it is wise to ask that all privileges be removed with the exception of medical privileges and then certain restrictions could be placed on those privileges. For example:
“You are authorized to come on post for prearranged medical appointments but you must be escorted to and from these appointments by your spouse or other designated representative. While on post you are not authorized to use any other facility.”
Privileges that can be revoked are: MWR, PX, Commissary, and on-post driving just to mention a few. The revocation of privileges must be made by the commander who has authority to revoke these privileges. In this case it is probably the garrison commander.