The April 9 exchange at a Capitol Hill hearing between Democratic Rep. Charlie Crist of Florida and Attorney General William Barr is at the heart of the latest attack on Barr, with many Democrats calling for his resignation.
Barr was asked if he knew anything about the report that there were frustrations being felt by special counsel Robert Mueller's team about the summary Barr released and the limited information it contained.
Barr said he did not know what it was about.
"It's clear that that wasn't the entire truth," NBC 10 Boston legal analyst Michael Coyne said of that answer.
Coyne says we now know Barr knew exactly what that was about based on a letter he received from Mueller, who was concerned that Barr's summary did not capture the context of his investigation.
"If, in fact, he knew that that was false — and it's obviously material," Coyne said, "That may be perjury."
At the Senate hearing Wednesday, Barr addressed the question of obstruction as it related to alleged attempts by Trump to shut the investigation down.
"The president could terminate that proceeding and it would not be a corrupt intent, because he was being falsely accused," Barr said.
Coyne does not agree.
"If the president and his staff intended to obstruct the investigation itself, then that could, in fact, be enough," he said.
Most revealing to Coyne was when Democratic Sen. Kamala Harris of California asked Barr if the president or anyone at the White House ever asked or suggested that he open an investigation of anyone.
After much pausing and back and forth about specific wording, Barr said he couldn't remember.
"Most experienced litigators looking at that would say that that whole series then was likely highly untruthful," Coyne said.
These hearings are filled with so much posturing and rhetoric — on both sides — that it can be hard to separate out the rule of law, Coyne said. He thinks the nation needs to hear from Mueller himself.