WASHINGTON, D.C. — House Intelligence Committee Chairman Adam B. Schiff expects new evidence to come out during the course of the Senate impeachment trial, adding a possible element of surprise to the proceeding and potentially complicating Republican efforts to reach a speedy conclusion.

“There’s going to be new evidence coming out all the time. And if this is conducted like a fair trial, then that new evidence should be admitted. If it’s relevant, if it’s probative, if it sheds light on the guilt or innocence of the president, then it should be admitted,” said Schiff, who was appointed Wednesday the lead House manager prosecuting the case against President Donald Trump.

Schiff, D-Calif., spoke to the Los Angeles Times on Wednesday as the House voted largely along party lines to approve Schiff and six other representatives, including Judiciary Committee Chairman Jerrold Nadler, D-N.Y., as managers in the trial.

The vote cleared the way for the impeachment articles to be forwarded to the Senate, where pretrial proceedings are expected to start Thursday.

Some Senate Republicans have indicated they think the scope of evidence weighed by the Senate should be limited to the evidence gathered during the House investigation. But Schiff predicted that Senate Majority Leader Mitch McConnell, R-Ky., would run into difficulty if he attempted to block information.

“It will be hard, I think, for the senators to ignore new and probative evidence,” Schiff said. “What are they gonna say? ‘We’re not going to look at that. We don’t want to see it. We’re going to close our eyes and close our ears and just pretend it didn’t happen or (that) we didn’t learn this fact’?

“So there are limits I think to the ability of Sen. McConnell to prevent meaningful evidence from being considered,” he said.

Speaker Nancy Pelosi, D-Calif., announced earlier Wednesday her choice of Nadler, Schiff, Democratic Caucus Chairman Hakeem Jeffries of New York, and Democratic Reps. Zoe Lofgren of California, Jason Crow of Colorado, Val Demings of Florida and Sylvia Garcia of Texas. Schiff, a former prosecutor, was tapped to lead the group.

“The emphasis is on litigation. The emphasis is on comfort level in the courtroom,” Pelosi said in describing the legal experience her choices brought to the proceedings.

The so-called House managers will give opening and closing statements, lay out the facts collected in the House investigation, and will cross-examine witnesses if they are allowed.

“The task before us is a grave one, but one demanded by our oath,” Schiff said on the House floor before the vote. “The House managers will take the case to the Senate and to the American people.”

The managers were confirmed 228-193. Rep. Collin Peterson of Minnesota was the only Democrat to vote against the resolution.

Pelosi was said to be aiming for a more diverse group than the 13 white men who acted as House managers during the impeachment trial of President Bill Clinton in 1999.

It’s a role that can make or break careers, and there was lobbying behind the scenes as members jostled for one of the plum positions. Pelosi got to decide how many managers to choose. After the Clinton trial, some of the Republican House managers faced a backlash; at least one lost his reelection bid —in an odd twist of fate, he lost to Schiff.

Later Wednesday, the managers will march across the Capitol building to notify the Senate that the articles of impeachment passed by the House in December are ready to be delivered. The Senate is tasked with weighing whether to remove Trump from office. It must vote before the articles can be officially presented. Once that vote occurs, Schiff and the other managers will march across the Capitol again, likely on Thursday, and read the articles to the gathered senators.

It is just the third time in U.S. history the Senate has been asked to decide whether allegations against a president warrant conviction and removal.

“President Trump has done nothing wrong. He looks forward to having the due-process rights in the Senate that Speaker Pelosi and House Democrats denied to him, and expects to be fully exonerated,” White House press secretary Stephanie Grisham said in a statement.

The articles, charging obstruction of Congress and abuse of power, were brought following an investigation into Trump’s attempt to get the president of Ukraine to open investigations into his political rivals at the same time he was withholding nearly $400 million in aid to Ukraine. Trump said that there was nothing improper about his conversations with the president or his handling of the aid.

The initial procedural motions of the Senate trial, including the swearing in of Chief Justice John G. Roberts Jr. to preside over the trial and of senators to a special oath as jurors, are expected to occur Thursday. Opening arguments from the House managers and the White House lawyers are expected to begin Tuesday.

Republicans control the Senate, and with 67 votes needed to remove a president from office, it is all but certain Trump will be acquitted.