Intelligence Committee Chairman Adam Schiff Adam Bennett SchiffOvernight Defense: House to vote on military justice bill spurred by Vanessa Guillén death | Biden courts veterans after Trump's military controversies Intelligence chief says Congress will get some in-person election security briefings Democrats, advocates seethe over Florida voting rights ruling MORE (D-Calif.), the lead House manager in President Trump's Senate trial, said Sunday that there is nothing Democrats could have done differently during the impeachment process.

Ahead of the Senate’s likely vote to acquit President Trump on Wednesday, Schiff defended Democrats’ methods and said that he and his colleagues “proved” their case.

“Look, there's nothing that I can see that we could have done differently because as the senators have already admitted, we proved our case. We proved our case,” Schiff said on CBS's “Face the Nation.” ADVERTISEMENT

“Now, the president's lawyers have said time and again, I think, hoping through sheer repetition to make something true that is in fact untrue, that the process in this impeachment was different than in Nixon and Clinton,” he added. “In fact, the president had the same due process rights, which he did not avail himself of in this process as in the prior ones.”

Schiff said the argument is “not an excuse that should be used by any senator for not fulfilling their obligation to hold a fair trial.”

“They're not spectators. They have control over the proceedings,” Schiff said of senators.

CBS’s Margaret Brennan asked Schiff if it was a “misstep” to drop the subpoenas of some witnesses, including for former White House national security adviser John Bolton John BoltonThe Hill's Morning Report - Sponsored by The Air Line Pilots Association - Pence lauds Harris as 'experienced debater'; Trump, Biden diverge over debate prep DOJ launches probe into Bolton book for possible classified information disclosures Gary Cohn: 'I haven't made up my mind' on vote for president in November MORE, during the House inquiry.

Schiff said it “wasn’t at all,” noting that it could have been a couple of years before courts reached a decision on Bolton.

“That means the president would have been able to cheat in the next election with impunity because they could have simply delayed and played out the clock,” he responded.

“While the president's lawyers are ... in the Senate court, saying the House should have made more efforts to overcome our obstructionism, they're making that remarkable argument, in court on the very same day they were making that argument, ... saying, 'Judge, you can't hear this case to compel Don McGahn to testify because you're not empowered to enforce congressional subpoenas,' ” he continued. “So they're arguing out of both sides of their mouth. The senators could see that. The senators should not allow them to get away with that.”

Only two Republicans joined Democrats in voting for a measure to consider calling new witnesses as part of the impeachment trial. A final vote on Trump’s removal will be held on Wednesday.

Trump will likely be acquitted by the Republican-majority Senate.