Please excuse me if I missed seeing someone post on this earlier, and for such a brief diary. But I just ran across this article on Politico.
The essential point of the article is that that language of the Constitution contains an exception to the pardon power granted the President. That Constitution explicitly states that the pardon power is limited only “except in cases of impeachment.” In other words, the article argues, once the President is impeached, the Constitution bars pardons for anyone convicted of an offense related to the premise of that impeachment. And, because the Constitution is silent with respect to the Senate action on the impeachment, the President’s acquittal does not nullify this prohibition.