Earlier this week, Obama said in an online interview with the German media outlet Der Spiegel that he "can't pardon somebody who hasn't gone before a court and presented themselves."
As P.S. Ruckman, editor of the Pardon Power blog, put it, "I just think what he may have better said is: ‘I prefer that he present himself to a court and then we'll talk turkey.' But technically in terms of the Constitution, there are no restrictions at all."
Mike Pompeo, President-Elect Donald Trump's pick for CIA director takes a draconian position on the issue. Instead of pardoning the NSA whistleblower, he supports imprisoning Snowden and following a course of law that would likely lead to the death penalty.
In an interview with C-SPAN earlier in the year, Pompeo said, "He should be brought back from Russia and given due process, and I think that the proper outcome would be that he would be given a death sentence for having put friends of mine, friends of yours, in the military today, at enormous risk because of the information he stole and then released to foreign powers."
Pompeo is notorious for his attitudes toward Islamic faith leaders, bulk surveillance and Guantanamo Bay. For instance, as he has said, the fact that many terrorist attacks come from people of a single faith should cause special obligations laid on leaders of that faith.
"Instead of responding, silence has made these Islamic leaders across America potentially complicit in these acts and more importantly still, in those that may well follow," Pompeo said in remarks on the House floor. These remarks were later called "false and irresponsible" by the Council on American Islamic Relations.