The House Homeland Security Committee is expected to approve articles of impeachment on Tuesday against Alejandro N. Mayorkas, the homeland security secretary, as Republicans race forward with a partisan indictment of President Biden’s immigration policies.

In what is expected to be a party-line vote, the panel is poised to charge Mr. Mayorkas with refusing to uphold the law and breaching the public trust in his handling of a surge of migrants across the United States border with Mexico, paving the way for a vote of the full House as early as next week.

Republicans are pressing forward despite staunch opposition from Democrats and an emerging consensus among legal scholars that they have produced no evidence that the secretary has committed high crimes and misdemeanors, the standard for impeachment.

The charges are all but certain to collapse in the Democratic-controlled Senate, where a two-thirds majority would be required to convict and remove Mr. Mayorkas. But if they pass the House, they will force an election-year trial in which Republicans will have the chance to air their indictment of Mr. Biden’s immigration policies.

In a letter to the panel on Tuesday, Mr. Mayorkas, whom Republicans did not allow to testify publicly in his own defense after a scheduling dispute, forcefully contested the charges, which accuse him of flouting laws requiring the deportation of migrants and stymieing congressional investigations by withholding information and lying about the state of the border.

“You claim that we have failed to enforce our immigration laws. That is false,” Mr. Mayorkas wrote. He said Republicans’ allegation that he obstructed their inquiries was “baseless and inaccurate.”