It depends on HOW violently he went against Trump. For instance (picture it) if he was pro-Hillary and anti-Trump, he wouldn't have a prayer of being pardoned.
If he has any useful purpose for Donnie, he will be protected to show Donnie how he protects his people.
That is why he did it and the only reason why. Arpaio would jump off a cliff if Trump ordered him to. That is the kind of pigs Trump needs by his side.
Too bad Arpaio is disgraced and hated by everyone on the planet besides Trumps base and Just Asking. She likes him too. HAAAA