Could Hillary Clinton pardon herself? Oh, sure. Would such a pardon, if challenged in the federal courts, withstand scrutiny? We would like to think not. In a 1996 Yale Law Journal article, Professor Brian Kalt seems to have handled the issue well enough.
Kalt notes, the "self-pardon" was "nowhere mentioned in the debates or in the English history that informed [the Framers of the Constitution]. As such, arguments derived from [them] are speculative at best." On the other hand, the federal government "is structured to prevent self-dealing, as evidenced by several constitutional provisions."
A member of Congress, for instance, cannot simultaneously hold another federal office, and cannot resign to take a job that was created or whose pay was increased during that term of Congress. Congress cannot legislate a pay raise for itself that takes effect before the next congressional election, and the presidential salary cannot be increased without an intervening presidential election. The President also cannot receive any other "emolument" from the United States besides his salary. In other words, federal lawmakers cannot create or enhance plush, high-paying government jobs for themselves, at least not without letting the voters review the decision. Another example is that the Chief Justice, not the Vice President, presides when an impeached President is tried. The other implicit constitutional prohibition against self-judging comes from the Expulsion Clause, which provides that either chamber of Congress can expel its members by a two-thirds vote. Although there is no explicit prohibitory language in the Clause against voting in one's own expulsion case, members of Congress do not do so, despite the high stakes and narrow margins of many expulsion votes.Kalt notes that, in other parts of the Constitution, "government officials are kept from acting as decisionmakers in matters that directly, materially, and uniquely affect them."
This disfavor for self-dealing in the structure of the government, explicitly recognized by the Framers themselves, provides important structural support for the claim that a President is forbidden from pardoning himself. The purported power of a President to pardon himself would be constitutionally anomalous and unprecedented in the constitutional structure. Such a power simply does not fit with the rest of the structure of the government established by the Constitution. It clashes with other established provisions in the Constitution that prevent self-judging and self-dealing.Kalt guesses an attempted self-pardon "would likely undermine the public's confidence in the presidency and the Constitution," but, "looking at the question from a cooler vantage point, the intent of the Framers, the words and themes of the Constitution they created, and the wisdom of the judges that have interpreted it all point to the same conclusion: Presidents cannot pardon themselves."
UPDATE: Four hours after this post, the Wall Street Journal's blog posted "Can a President Self-Pardon?" by Jacob Gershman. It also refers to Professor Kalt (a kind of Christmas miracle), but Richard Posner as well.