There is no guarantee. There is really no one that could even make such a guarantee. Opinions of DOJ change with administrations. The president could issue a

There is no guarantee. There is really no one that could even make such a guarantee. Opinions of DOJ change with administrations. The president could issue a pardon after the fact. Congress could make a law. Perhaps the executive could find some loophole to deputize people into US Cybercom but that would likely make them a lawful combatants which has other entanglements.