Senate Dismisses First of Two Impeachment Charges Against Mayorkas

The Senate on Wednesday dismissed the first of two articles of impeachment against Alejandro N. Mayorkas, the homeland security secretary, voting along party lines before his trial got underway to sweep aside the charge accusing him of failing to enforce immigration laws.

By a vote of 51 to 48, with one senator voting “present,” the Senate ruled that the charge was unconstitutional because it failed to meet the constitutional bar of a high crime or misdemeanor. Republicans united in opposition except for Senator Lisa Murkowski of Alaska, the lone “present” vote, while Democrats were unanimous in favor, after arguing that a cabinet member cannot be impeached and removed merely for carrying out the policies of the administration he serves.

“To validate this gross abuse by the House would be a grave mistake and could set a dangerous precedent for the future,” said Senator Chuck Schumer of New York, the majority leader.

Republicans, for their part, warned that the dangerous precedent was the one that Democrats set by moving to skip an impeachment trial altogether, which they argued was a shirking of the Senate’s constitutional duty. They tried several times to delay the dismissal, failing on a series of party-line votes.

“Tabling articles of impeachment would be unprecedented in the history of the Senate — it’s as simple as that,” said Senator Mitch McConnell of Kentucky, the minority leader.

Democrats moved immediately to strike down the second article of impeachment against Mr. Mayorkas, alleging a breach of the public trust, thus skipping the trial altogether. A vote was expected later on Wednesday.