President Donald Trump’s impeachment defense team on Tuesday concluded their third day of oral arguments by attacking the impeachment charges brought by House Democrats. They also sought to undermine leaked details from an upcoming book by former national security adviser John Bolton, who reportedly wrote that Trump told him he would not release aid to Ukraine’s military until the country launched an investigation into a U.S. political rival.

“You cannot impeach a president on an unsourced allegation,” Trump lawyer Jay Sekulow said on the Senate floor, referring to reports of Bolton’s manuscript. “I’d call that inadmissible.”

With the opening presentations over, the Senate will next submit questions for the House managers and defense teams to answer, before debating whether to hear from witnesses.

Here are four key moments from Trump’s defense team’s last day of opening arguments:

1. Abuse of power charge is too ‘malleable,’ Philbin argues

Deputy White House counsel Patrick Philbin worked to undercut the articles of impeachment brought against the president. Philbin argued that the framers of the Constitution would not have approved of the standard used by Democrats in this case.

“What we see in the House managers’ charges and their definition of abuse of power is exactly antithetical to the framer’s approach,” Philbin said. “Because their very premise for their abuse of power charge is that it is entirely based on subjective motive, not objective standards, not predefined offenses.”

2. Impeachment isn’t ‘a game of leaks’

During his remarks, Sekulow took a jab at the remarks made by Bolton in his forthcoming book, revelations of which first appeared in The New York Times, citing “multiple people” who described Bolton’s account.

Impeachment “is not a game of leaks and unsourced manuscripts,” Sekulow said. “That’s politics, unfortunately, and [Alexander] Hamilton put impeachment in the hands of this body, the Senate, precisely and specifically to be above that fray.”

“To lower the bar of impeachment based on these articles of impeachment would impact the functioning of our constitutional republic and the framework of that constitution for generations,” he added.

3. ‘That’s politics,’ Sekulow says of House impeachment process

Sekulow criticized a decision by House Democrats to delay transmitting the articles of impeachment to the Senate after the House impeached Trump in December. Sending the articles over would trigger the start of the Senate trial, and for several weeks, Speaker Nancy Pelosi said she would only send them until she could ensure the Senate trial would be fair.

“Remember the whole idea that this was a dire national security threat, a danger to our nation? We had to get this over right away, it had to be done before Christmas,” Sekulow said in his remarks. Sekulow questioned why House Democrats refused to transfer the articles, if they felt the country was in jeopardy.

4. Cipollone uses Democrats’ words from Clinton impeachment

Trump’s legal team played video clips of Democratic lawmakers speaking during then-President Bill Clinton’s 1998 impeachment process.

“There must never be a narrowly voted impeachment or an impeachment supported by one of our political parties and opposed by the other,” Rep. Jerry Nadler, D-N.Y., one of the House managers, said in a clip played Tuesday from Clinton’s impeachment. “Such an impeachment would produce the divisiveness and bitterness in our politics for years to come.”

“You were right, but I’m sorry to say were also prophetic,” Cipollone said, addressing the lawmakers who were quoted in a reel of clips. “I think I couldn’t say it better myself, so I won’t.”