BOSTON – U.S. Rep. Lori Trahan on Wednesday joined other members of the state's congressional delegation in calling for impeachment proceedings against President Donald Trump.

Trahan, who had been reluctant to support a formal inquiry, said it was former special counsel Robert Mueller's testimony before the House Judiciary Committee on Wednesday, as well as mounting evidence that the Republican president may have broken the law, that changed her mind.

"This is not a decision I came to lightly," Trahan, a Westford Democrat, said in a statement. "As a staffer during the Clinton impeachment, I’ve seen firsthand how disruptive this process can be for our nation. But no president, including this one, is above the law."

Trahan said Mueller's testimony indicates "ample evidence that the president broke the law by repeatedly engaging in efforts to obstruct the investigation into Russian interference in the 2016 election."

"It is up to Congress to act to determine the truth," she added.

The freshman congresswoman's stance puts her at odds with House Speaker Nancy Pelosi, who has made clear she will not pursue impeachment, for now.

But Trahan has company in the state's 11-member, all-Democratic congressional delegation -- including Sen. Elizabeth Warren, and Reps. Seth Moulton and Ayanna Pressley -- who have called for impeachment proceedings.

Moulton, who like Warren is running for president, makes the case that Congress can no longer ignore the president's efforts to obstruct investigations into potential wrongdoings.

"It's our constitutional duty to have this debate in the House of Representatives," he told reporters in a teleconference following Mueller's testimony. "It's not the right time for a vote on impeachment but we absolutely have to begin the proceedings."

Other members of the delegation -- Sen. Ed Markey, and Reps. Stephen Lynch, Katherine Clark and Richard Neal -- while all critical of the president's leadership, have stopped short of calling for impeachment.

Trahan and Clark were among those joined 95 other House Democrats who voted against a move last week to block a measure filed by Democratic Rep. Al Green of Texas to initiate articles of impeachment against Trump. Green's impeachment proposal was ultimately defeated.

Pressure has increased on Democrats following Mueller's report in which he noted multiple White House efforts to obstruct investigations into Russian meddling in the 2016 presidential elections.

On Wednesday, Mueller reiterated that charging Trump with a crime was "not an option" because of federal rules, but that his report did not exonerate the president.

Mueller described Russian government efforts to interfere in American politics as among the most serious challenges to democracy he had encountered in his decades-long career - which included steering the FBI after the Sept. 11 terrorist attacks.

During a televised press conference Wednesday evening, Pelosi said Mueller's testimony provided "damaging evidence" but said she wasn't yet prepared to initiate impeachment proceedings.

"We want to have the strongest possible case to make a decision as to what path we are going down," the Democrat told reporters. "But if it comes to a point where the code of silence and obstruction of justice and the cover-ups in the White House prevents us from getting that information, that will not prevent us from going forward."

The U.S. Constitution allows Congress to remove presidents before their terms are finished if enough lawmakers vote to say that they committed "treason, bribery, or other high crimes and misdemeanors.”

Removal requires a simple majority vote in the House and a trial in the Senate, where two-thirds of the upper chamber would have to vote to convict.

So far, none of the state's congressional lawmakers have said they oppose impeachment.

Meanwhile, the state's Republican Party called on Trahan and other members of the congressional delegation to "apologize" to Trump following Mueller's testimony.

"These Democrats owe President Trump an apology, as today's hearings were a disaster for them," MassGOP chairman Jim Lyons said in a statement. "The collusion narrative has collapsed spectacularly, and these members of our Massachusetts congressional delegation are refusing to admit it."

Christian M. Wade covers the Massachusetts Statehouse for North of Boston Media Group’s newspapers and websites. Email him at