Rep. Tom McClintock, R-CA, used his line of questioning to press Hur over whether it was "OK if I take home top secret documents, store them in my garage and read portions of them to friends or associates?"

"Congressman, I wouldn't recommend it," Hur said dryly. "But I don't want to entertain any hypotheticals."

"But you've essentially said so in your report!" McClintock responded. "And certainly it would be exculpatory if I simply told you, 'Hey, I'm getting old. I don't remember stuff the way I used to.'"

McClintock then argued that Hur had decided not to prosecute Biden "for the same offense" Trump has been charged with in his case involving unlawful retention of classified materials and efforts to obstruct the government's investigation -- even though Biden was not accused of obstruction.

"Congressman, I do address as I was required to as a prosecutor a relevant precedent in the form of the allegations in the indictment against former President Trump," Hur said. "I set forth my explanation in my assessment and comparison to those precedents in my report, and I am not here to comment any further."

Under questioning from lawmakers, Republicans pressed Hur on how the evidence he gathered failed to indicate criminal behavior, while Democrats pressed him on comparisons between Biden's conduct and Trump's.

Rep. Kelly Armstrong, R-ND, began by outlining some of the underlying facts of Hur's investigation into Biden's handling of classified documents -- probing his determination that Biden shouldn't be charged with "willfully retaining national defense information," even as his report outlined evidence of various instances where he said Biden either knew he had classified materials or discussed having it with his ghostwriter.

"Congressman, part and parcel of a prosecutor's judgment as to whether or not a conviction is the probable outcome of trial is assessing how the evidence identified during the investigation lines up with the elements and what proof can be offered to a jury during a trial," Hur said.

"Sure, but this well-meaning elderly old man has nothing to do with the underlying elements of the crime?" Armstrong asked.

"It certainly has something to do with the way that a jury is going to perceive and receive and consider and conclude -- make conclusions based on evidence at trial," Hur responded.

Hur swatted away questions from Rep. Jerry Nadler, the ranking Democrat on the panel, who multiple times looked to have the special counsel comment or compare Biden's handling of documents to Trump's own legal issues.

Hur replied when specifically about allegations against Trump, "I am not intimately familiar with the facts relating to former President Trump."

In his opening statement, former special counsel Robert Hur defended how he characterized Joe Biden's memory in his report on the president's handling of classified documents released in February.

"My assessment in the report about the relevance of the president's memory was necessary and accurate and fair," Hur said. "I did not sanitize my explanation."

Hur addressed his criticism of Biden's memory in the report head on, saying, "I understood that my explanation about this case had to include rigorous, detailed, and thorough analysis. In other words, I needed to show my work."

Hur added, "I knew that for my decision to be credible, I could not simply announce that I recommended no criminal charges and leave it at that. I needed to explain why."

Hur went on to argue that purpose of his investigation was to determine whether or not Biden "willfully" retained or disclosed classified information, and that he "could not make that determination without assessing the President's state of mind."

"These are the types of issues prosecutors analyze every day," Hur said. "And because these issues were important to my ultimate decision, I had to include a discussion of them in my report to the attorney general."

"Did Joe Biden unlawfully retained classified information? The answer? Yes, he did," House Judiciary Chairman Jim Jordan, R-Ohio, said in opening the hearing. "Page one of Mr. Hur's report he says this: 'Our investigation uncovered evidence that President Biden willfully retained and disclosed classified materials after his vice presidency when he was a private citizen.'"

Yet while it's true that Hur's report stated he found evidence that Biden retained classified information, he stopped short of concluding Biden knowingly violated the law and determined he would not be able to prove Biden's guilt to a jury beyond a reasonable doubt.

Jordan then played out video clips of Biden responding to the findings in Hur's report, saying he expects today's hearing will give Hur a chance to respond to Biden's statements that either downplayed Hur's findings or attacked him directly.

Rep. Jerry Nadler, the ranking Democrat on the panel, sought to highlight discrepancies in Biden's conduct compared with former President Donald Trump's, saying, "Simply put, President Biden had the mental acuity to navigate this situation. President Trump did not."

Nadler then played a lengthy clip reel of Trump's perceived verbal slips on the campaign trail, saying. "That is a man who is incapable of avoiding criminal liability. A man who is wholly unfit for office, and a man who, at the very least, ought to think twice before accusing other of cognitive decline."

At the end of the Trump clip reel, some lawmakers, including some Republicans, were observed snickering at his remarks.