As co-blogger Jonathan Adler points out, Libertarian Party presidential candidate Bob Barr is one of many people who confuse the theory of the "unitary executive" with the claim that the executive has virtually unlimited power. Barr argues that "McCain has endorsed, in action if not rhetoric, the theory of the 'unitary executive,' which leaves the president unconstrained by Congress or the courts." In reality, the unitary executive argument is a theory about the distribution of executive power, not its scope. I addressed this crucial distinction in more detail in this post. I hate to quote myself, but I don't think I can improve on what I said then:

The idea of the unitary executive is simply that whatever power the executive branch has should be concentrated in the hands of the president. There can be no executive officials (such as the independent counsel) who are not subject to presidential control and removal. As Article II of the Constitution states, "the executive power [of the federal government] shall be vested in a President of the United States." It does not grant any executive authority to officials not under presidential control.

This is perfectly consistent with simultaneously believing that the scope of executive power is relatively narrow, and that the president has no authority to ignore laws enacted by Congress, including those that constrain many military and foreign policy decisions. Congress can pass a variety of laws stating that no one in the executive branch - including the president - can do X....

Constraining presidential authority in this way does not go against the theory of the unitary executive. What Congress cannot do without contradicting the theory is pass a law allocating authority to decide whether to do X to executive officials who are exempted from presidential control and removal.

Barr's claim that McCain supports unlimited executive power "unconstrained by Congress or the Courts" is also strange in light of the fact that McCain sponsored the McCain Amendment forbidding the use of torture, one of the best-known congressional efforts to cut back on the Bush Administration's extreme assertions of executive authority.

I am no fan of McCain, who has many genuine shortcomings from my libertarian perspective. To the extent that I support his candidacy, it is primarily because a McCain victory is the only hope for preserving divided government, which is one of the most important constraints on the growth of the state. Nonetheless, it is not true that McCain has endorsed unconstrained executive power.

UPDATE: TalkLeft criticizes this post, arguing that the Bush Administration has claimed that the unitary executive theory does indeed justify unlimited presidential power. TalkLeft's post gives several examples of Bush Administration officials claiming extremely broad presidential power. However, none of the quotes in question claim that power on the basis of the theory of the unitary executive. One of the quotes mentions the "unitary executive branch" in passing, but rests its claim of broad executive authority on the Commmander in Chief Clause. And even if the Bush Administration has misused the term "unitary executive" on occasion, that is no reason for the rest of us to do so.

The post also cites a 2001 speech by Samuel Alito arguing that "all federal executive power is vested by the Constitution in the President." This statement, of course, is clearly compatible with strong judicial and congressional limits on executive power. Executive power can be narrow, yet still be entirely vested in the hands of the president. As Alito himself stated at his confirmation hearing:

The question of the unitary executive . . . does not concern the scope of executive powers, it concerns who controls whatever power the executive has. You could have an executive with very narrow powers and still have a unitary executive.

Finally, TalkLeft claims that the theory of the unitary executive (even as I construe it) is "self-evidently wrong" because of the Spending Clause and the Senate's power to confirm certain presidential appointees. I don't see how the existence of the clauses invalidates the theory that all executive power lies in the hands of the president. Rather, the existence of the Spending Clause simply shows that the power to control federal spending is not part of the power of the executive branch. Similarly, the Senate's confirmation power simply allows the Senate to veto certain presidential appointments. To use Alito's terminology, neither says anything about the question of "who controls whatever power the executive has."