Tie-breaking votes in the Senate, no Vice-President

One of the few Constitutionally-assigned duties of the Vice-President of the USA is to cast tie-breaking votes in the Senate. What happens if a Senate vote ties and the Vice-Presidency is vacant? I understand this is unlikely to come up these days since the passage of the 25th Amendment allows a vacancy in the Vice-Presidency to be filled (and the filibuster has made tie votes rarer than hen’s teeth anyway). But is there any legislation as to what would be done, or has it happened before? The Vice-Presidency has been vacant for significant periods of time prior to the passage of the 25th Amendment (eg the entirety of the John Tyler and the Andrew Johnson Administrations).

A tie vote is not a majority, so the motion fails. That’s about it.

I concur.

That’s how it works in the Senate of Canada and I think in the House of Lords. There’s no provision for a tie-breaking vote, and a motion must pass by a majority. A tie means the motion is defeated. (Which is why Canada does not have any criminal prohibitions on abortion.)

… Which goes along with a constitutional convention / rule, that motions must be framed so action results only from an affirmative vote.

Otherwise you could get an arbitrary motion past a tie just by reversing the sense. I suspect (from what I’ve heard about the federal system) that there is no absolute rule – it wouldn’t be needed if the VP had a tie-breaker vote.

Does anyone know?

We had quite a discussion in one thread where a couple people thought you could make a motion to not do something and if it failed, the body was required to take that action. The couple of examples they pointed to were not the motions they claimed however.

According to this from the US Senate:


Given the first quote, the second one makes sense since having it otherwise would be allowing the president pro tempore to vote twice on an issue.

Thanks all, sounds like the answer is most likely that no one would have tie-breaking vote powers, and tied votes would simply fail to pass the motion. Sounds reasonable to me.

However, if the tie happened on a vote to choose the next VP (assuming the electoral college had failed to produce a majority) my understanding is that that tie would be broken by the previous VP since he leaves office only when his successor has been chosen. Great fun. Of course, what would be going on in the HR would be no fun at all.

The true President of the Senate (the VP) can vote to make a tie (the motion fails) or break a tie (presumably in the VP’s favor).

No, the VP can only vote if there’s a tie.

That can’t be right, because the Constitution says

So the VP can only vote in the case that there is already a tie.

I sit corrected.