Could an Acting President preside over the Senate?

Suppose the President is temporarily incapacitated due to illness, the Vice-President invokes the 25th Amendment and becomes Acting President. Then the Senate splits 50-50 on an issue. Can the Vice-President, while acting as President, preside over a Senate session and cast a tie-breaking vote?

Probably not. The Constitution (art. I, sec. 3) provides that

This language implies that, when the Vice President is acting as President, the Senate president pro tempore displaces the Vice President as the Senate’s regular presiding officer.

I do not know, but I would assume it would go to the Speaker of the House to succeed to Acting Vice-President and serve as President of the Senate. I would think that once the Vice-President assumes the duties (temporarily) of President he would no longer be allowed to perform those of Vice-President. [/WAG]

:rolleyes: Absolutely not. There is no provision in the Constitution, laws, or legislative rules under which an officer of one chamber can succeed to an office in the other chamber; more to the point, the very notion is contrary to the concept of a bicameral legislature.

And there is no such thing as an “acting Vice President.” The Vice President has but two constitutional duties: presiding over the Senate, and succeeding the President. When the Vice President isn’t presiding over the Senate, the Senate elects a president pro tempore for the purpose of filling in; it’s the only reason that the office of Senate president pro tempore exists. And presidential succession beyond the Vice President is governed by the Presidential Succession Act, which names the officers who follow the Vice President in the line of succession.

You forgot protecting the space-time continuum.

Anyway, I agree. I see no reason why the Vice President would have to be filled-in for during a temporary absence for the President. If the absence was long enough, of course, the change might be made permanent and then the new President could pick a new Vice President, like Ford and Rockefeller, but there is no need for a Vice Presidental succession. Either the President is able to choose a new VP or the Presidental Succession Act will kick in, and then that new President will be able to choose a new VP.

Is he able to perform both duties at the same time? The OP was asking about who breaks a deadlocked senate vote when the VP is already acting president. A tie vote at 50-50 would indicate that the President Pro Tempore of the Senate has already voted, so he can’t do it. The President is not allowed to do it. As the Vice-President is currently Acting President, wouldn’t he be excluded?

As I said, I was just guessing. The ideas expressed in my earlier post seemed to make sense to me.

Yes, he (the Acting President) would be excluded. In which case the motion in question would fail as a majority could not be obtained.

No big deal. Motions fail in the Senate all the time. Hooray for democracy!