What To Watch For As Trump's Legal Team Resumes Its Impeachment Defense

President Trump's defense team is expected to maintain Monday, the second day of its arguments in the Senate impeachment trial, that the president was legally justified in freezing military assistance to Ukraine and that the case against Trump presented by Democrats does not clear the bar of an impeachable offense.

The arguments come a day after a report by The New York Times that Trump directly told his former national security adviser John Bolton in August that he would hold up aid to Ukraine until the country launched investigations into his political rivals. The report was based on Bolton's forthcoming book, a draft of which had been sent to the White House as part of a standard review process.

Two GOP Senators, Mitt Romney of Utah and Susan Collins of Maine said Monday the revelations about Bolton's book have made it more likely that Senators will want to call Bolton to testify.

"I think it's increasingly likely that other Republicans will join those of us who think we should hear from John Bolton," Romney said, noting that he would make his final decision on the issue after hearing from Trump's defense.

Collins tweeted that the reports about Bolton's book "strengthens the case for witnesses and prompted a number of conversations among my colleagues."

A spokesman for the National Security Council said no one at the White House other than people at the NSC had reviewed Bolton's book.

"Ambassador Bolton's manuscript was submitted to the NSC for pre-publication review and has been under initial review by the NSC," NSC spokesman John Ullyot said in a statement. "No White House personnel outside NSC have reviewed the manuscript."

NPR has not seen a draft of the manuscript. Trump denied Bolton's account in a series of tweets.