Does the Vice-President retain their tiebreaking vote during an impeachment trial of the President?

Question

The Vice-President is the President of the Senate by the US Constitution. As President of the Senate, the Vice-President is empowered to preside over the Senate and cast a tie-breaking vote. The Constitution also specifies that the Chief Justice presides over an impeachment trial of the President. In such a case, does the Vice-President still retain the right to cast a vote when the vote is equally divided in the Senate during an impeachment trial?

Such a tie could potentially occur during a procedural vote or a similar question other than the question on whether to convict the President. This question does not include in its scope the actual vote to convict which would obviously not reach the two-thirds threshold if the Vice-President is casting a vote (aside from the pathological case when all Senators abstain or all but two Senators abstain, but quorum is still present).

Answer 1

Does the Vice-President retain their tiebreaking vote during an impeachment trial of the President?

No, the vice president has no defined role in the impeachment trial of the president.

It is possible that the vice president could relinquish the chair to the chief justice, but, even that is not required.

The chief justice may cast a tie-breaking vote on procedural matters. Procedure and Guidelines for Impeachment Trials in the United States Senate, Chief Justice as Presiding Officer, pp. 40-42.

The Chief Justice has voted in the case of a tie in an impeachment trial on two occasions. On March 31, 1868, a motion was made that the Senate retire for consultation. The yeas were 25 and the nays were 25, and the Chief Justice voted in the affirmative. At this point the Senate retired to its conference chamber.

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During the next day’s proceedings, Senator Sumner again raised the issue of the right of the Chief Justice to vote. During the reading of the Journal, he proposed an amendment to the Journal as follows: "It appearing from the reading of the Journal of yesterday that on a question where the Senate were equally divided the Chief Justice, presiding on the trial of the President, gave a casting vote, it is hereby declared that, in the judgment of the Senate, such vote was without authority under the Constitution of the United States." This was rejected by a vote of 21 yeas, 27 nays. Thus the Senate turned down each attempt to prevent the Chief Justice from voting, and in a subsequent action concerning a motion for adjournment, the vote being yeas 22, nays 22, the Chief Justice voted in the affirmative, deciding the issue. This vote was not challenged.

At the end of the trial of President Johnson, however, another occasion arose on a motion to adjourn to a date certain when the vote was tied 27 to 27 and the Chief Justice refrained from voting.

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See also How many Senators must vote to override specific judgments of the Chief Justice in an impeachment trial of the President?.

Answer 2

No.

When the Constitution was created, the runner-up in the presidential race became vice president. As such, there was no possible way for a presidential impeachment to occur without the appearance of bias on the vice president's part: he and the president were likely of different parties, different ideologies, etc, and the vice president would be the direct benefactor of the president's removal from office. So to avoid this impropriety, the Constitution installed the Chief Justice of the Supreme Court in that role (in addition to that of judge at a jury trial), assuming that the solemnity of the Chief Justice's role would make any presidential impeachment trial above contempt. While we have altered the vice presidential role to be chosen by the president (and allowed senators to be directly elected and thus have the potential for partisanship), we have not significantly altered the presidential impeachment laws to reflect this.