Photo/IllutrationDaniel Richman, professor at Columbia Law School, speaks about Comey memos in New York. (Tadashi Sugiyama)

NEW YORK--A Columbia Law School professor and former federal prosecutor admitted he was involved in disclosing one of former FBI Director James Comey’s memos documenting his exchanges with President Donald Trump to The New York Times.

“I thought it was important this time around to get a story of a president trying to tamper with the machinery of justice out,” Daniel Richman said in a recent interview with The Asahi Shimbun.

Comey was dismissed in early May when the FBI investigation was under way over whether members of the Trump campaign team colluded with Russian officials in their meddling in the U.S. presidential election.

The New York Times reported on the existence of the memos on May 16, a week after Comey's firing.

Following the report, criticism of Trump has soared and calls demanding a fair investigation into the alleged links between his campaign and Russia have grown.

That led the Justice Department to appoint Robert Mueller, a former FBI director, as special counsel to oversee the probe.

A focus of the Russia investigation is whether Trump obstructed justice.

As the investigation led by the special counsel continues, testimony by an individual who helped bring to light the memos that could serve as evidence pointing to the pressure exerted by the president is important.

Richman and Comey have remained close friends for a long time. They both worked in the U.S. Attorney's Office for the Southern District of New York 30 years ago.

“He gave me that memo so that I could be in a position to say to The New York Times I had seen it,” Richman said, adding that Comey was aware of whom the professor was giving it to.

“It was his decision that the substance of that meeting (on Feb. 14) be communicated to the Times,” he added.

Comey's memos included one in which Trump asked the FBI director to drop the investigation into Michael Flynn, his former national security adviser.

“I certainly knew it was something that the country really needed to know about,” he said.

The professor said he submitted the Comey memos to the FBI.

Trump criticized the leaking of the memos to the media, arguing they contained classified information.

But Richman countered by saying the “memos I received were not, at the time, classified.”

“Anyone with the slightest knowledge of the law and the facts will know that this was a legal action,” he said.