It might be easier to comprehend to say something to the effect of, the Staff has maximum levels of all 7 lawbreaker powers (Though I don't think it would protect against the outergates Law). Then, since its bestowing those as temporary powers on its user, he doesn't have to worry about taking Lawbreaker when he uses it. Same basic thing though.
But I do think there should be a limit to how many times it can protect you per session.