Who is Robert Hur, the ex-special counsel who oversaw the DOJ's Biden probe?

Robert Hur, who as special counsel conducted the yearlong probe into President Joe Biden's handling of classified documents, testified Tuesday before members of the House Judiciary Committee about his findings.

Hur, who was previously nominated by then-President Donald Trump as U.S. attorney for the District of Maryland, ultimately absolved Biden of legal culpability -- writing in his 388-page report published last month that he would not recommend charges against him despite uncovering evidence that the president "willfully retained" classified materials.

In the course of explaining his rationale for that conclusion, Hur said in the report that a potential jury would likely find Biden to be a "sympathetic, well-meaning, elderly man with a poor memory."

Republicans on the House Judiciary Committee summoned him to testify in a public setting to examine the findings of his yearlong probe.

Hur defended his decision during Tuesday's hearing, saying, "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."

He argued that the 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."

Attorney General Merrick Garland last year appointed Hur to oversee the DOJ's investigation into Biden's handling of classified documents, at the time saying he was confident Hur will "carry out his responsibility in an even-handed and urgent manner and in accordance with the highest traditions of this department."

Hur was a litigation partner at Washington, D.C., law firm Gibson, Dunn & Crutcher at the time of his appointment.

Prior to joining the firm, Hur oversaw one of the largest U.S. attorney's offices in the nation as the chief federal law enforcement officer in Maryland from 2018 to 2021. He was appointed by Trump and unanimously confirmed by the U.S. Senate to the role.

The move marked a return to the office; Hur was an assistant U.S. attorney in the District of Maryland from 2007 to 2014, during which he received the Attorney General's Distinguished Service Award for "superior performance and excellence as a lawyer," according to the DOJ.

Hur briefly worked in a senior leadership position for the Department of Justice from 2017 to 2018, until his U.S. attorney appointment. As the principal associate deputy attorney general, he was the principal counselor to Deputy Attorney General Rod Rosenstein and served as the point person coordinating with special counsel Robert Mueller's office in the investigation of Russian interference in the 2016 presidential campaign.

Rosenstein later recommended Hur to take his former position leading the U.S. Attorney's Office in Maryland.

"I think the most important thing to know about Rob Hur is he understands the need to ignore politics and focus on what matters in the Department of Justice and that is you make decisions based upon the facts, the law and the applicable Department of Justice policies. And Rob knows he's gonna come in for a lot of criticism from both sides, but he understands you need to ignore that and do the right thing," Rosenstein said in a statement following Hur's appointment as special counsel.

Hur also served as special assistant and later counsel to Christopher Wray, then-Assistant Attorney General in charge of the Justice Department's Criminal Division, prior to his work as an assistant U.S. attorney in the District of Maryland.

Hur began his legal career as a law clerk for Chief Justice William Rehnquist and Judge Alex Kozinski of the U.S. Court of Appeals for the Ninth Circuit. He received his bachelor's degree from Harvard College and law degree from Stanford Law School.

Hur's appointment as special counsel follows that of Jack Smith, a longtime federal prosecutor and former head of the Justice Department's public integrity section, who is overseeing the DOJ's investigation into former President Donald Trump's handling of classified materials after leaving office.

ABC News Alexander Mallin contributed to this report.