Comment by lesuorac
But none of that has to do with a president's own qualified immunity.
ICE isn't inheriting the president's qualified immunity; they have it because they're government employees. It doesn't matter if they're acting in the presidents interests or not and for state employees if they're acting in the governors interests or not.
Pardon is a very clearly enumerated power of the president so any usage of it is very clearly legal (although typically undesirable).
The problem with the presidential pardon is that it enables the president or his accomplices to carry out any amount of federal crimes. See Iran-Contra.