Former Lawmakers Pressure Congress to Reject Trump’s Emergency Declaration

WASHINGTON — More than 25 former Republican lawmakers and nearly 60 former senior national security officials appealed to Congress on Monday to kill President Trump’s declaration of a national emergency on the Mexican border, countering Republican leaders’ effort to hold down defections Tuesday on a scheduled House vote to block the president.

“It has always been a Republican fundamental principle that no matter how strong our policy preferences, no matter how deep our loyalties to presidents or party leaders, in order to remain a constitutional republic we must act within the borders of the Constitution,” wrote the former members of Congress, including Senators John Danforth, Chuck Hagel, Olympia J. Snowe and Richard Lugar, who implored Republicans to protect Congress’s constitutionally mandated power of the purse.

The security officials said there is neither a “documented terrorist or national security emergency at the southern border” nor an “emergency related to violent crime.”

The president’s assertions “are rebutted not just by the public record, but by his agencies’ own official data, documents, and statements,” the officials, including Madeleine Albright, the former secretary of state, and John O. Brennan, the former C.I.A. director, said in their declaration.

“Under no plausible assessment of the evidence is there a national emergency today,” they wrote.

The House’s vote Tuesday on a declaration of disapproval will force Republicans to choose between the congressional prerogative over federal spending established in the Constitution and a president determined to go around the legislative branch to secure funds for a border wall that Congress has refused to grant. The resolution is expected to sail through on Democratic votes, but significant Republican defections would give it momentum in the Senate and could raise the specter — however remote — that Congress could override Mr. Trump’s promised veto, should it reach his desk.

On Monday, Mr. Trump trained his attention on the Senate, where only four Republican votes are needed to pass the measure, should Democrats remain united, as expected. Mr. Trump warned Republicans not to “fall into the Democrats ‘trap’ of Open Borders and Crime!”

Several conservative senators have expressed concern that Mr. Trump’s declaration is setting a precedent that could be used by a Democratic president determined to secure funds that Congress won’t give.

Top House Republicans are urging their members to focus on what they say is a legitimate need for border security money and the precedent set by other presidents who have declared their own national emergencies, according to one Republican aide. Representative Steve Scalise of Louisiana, the Republican whip, and other members of his vote-counting team will lobby for votes against the resolution during a session Monday night.

Only one House Republican, Representative Justin Amash of Michigan, has signed on to the resolution to block the declaration, scorning the idea that congressional Republicans who attacked President Barack Obama’s use of executive powers “now cry out for a king to usurp legislative powers.”

Several lawsuits have already been filed challenging the merits of the declaration, but the easiest way for Congress to counter it is through the resolution, under the National Emergencies Act of 1976. Once it passes the House, the Senate is required under the law to take it up within 18 days.

House Republicans are confident that even with defections supporting the resolution on Tuesday, they will muster enough conservative support to sustain a presidential veto.

Democrats frame Tuesday’s vote as a referendum on protecting the separation of powers and Congress’s constitutional right to determine federal spending levels.

“This is about the oath we take to protect and defend the Constitution of the United States,” said Speaker Nancy Pelosi at a news conference in Laredo, Texas, on Friday. “Our founders very wisely placed in the Constitution provision for the separation of powers.”

Members of the House Appropriations Committee will hold a hearing on Wednesday to examine the impact of the declaration on military construction and readiness, and members of the House Judiciary Committee will hold a hearing on Thursday in part to examine Mr. Trump’s use of powers under the National Emergencies Act.