An IRS supervisory special agent has now gone public in an interview with CBS about interference in a case in which he was involved. Gary Shapley said that he became so concerned about how the case was being handled by the Department of Justice that he just had to sound the alarm.

CBS has determined that the case Shapley is talking about is the Hunter Biden case.

A veteran IRS supervisory special agent says he personally witnessed interference by Biden's DOJ in the Hunter Biden criminal investigation — contradicting AG Merrick Garland's sworn testimony pic.twitter.com/ieKq6lvmdG

— RNC Research (@RNCResearch) May 25, 2023

The letter that Shapley’s lawyers sent to Congress on Monday alleges “irregularities” in the handling of the investigation.

“There were multiple steps that were slow-walked — were just completely not done — at the direction of the Department of Justice,” said Gary Shapley, a 14-year veteran of the agency, who spoke exclusively to CBS News chief investigative correspondent Jim Axelrod on Tuesday. “When I took control of this particular investigation, I immediately saw deviations from the normal process. It was way outside the norm of what I’ve experienced in the past.” [….]

“Each and every time, it seemed to always benefit the subject,” Shapley said. “It just got to that point where that switch was turned on. And I just couldn’t silence my conscience anymore.”

Shapley is a supervisory special agent with the IRS’s criminal investigations department, currently overseeing a team of 12 agents who specialize in international tax and financial crimes. Previously, he was an officer with the National Security Agency’s Office of the Inspector General. He was assigned to a “sensitive” investigation in January 2020, and within months, he said he grew concerned about how the Justice Department was handling the investigation. CBS News has learned that was the Hunter Biden probe. Shapley says he began documenting his concerns around June 2020.

“For a couple years, we’d been noticing these deviations in the investigative process. And I just couldn’t, you know, fathom that DOJ might be acting unethically on this,” he said.

Shapley said that after a meeting in October, his team was effectively shut out of the investigation, and that’s why he came forward. “It just got to that point where that switch was turned on, and I just couldn’t silence my conscience anymore.”

Shapley can’t talk more or go into greater details until he gets whistleblower protections. He will be testifying before the House Ways and Means Committee on Friday in a closed hearing. Shapley has made whistleblower disclosures to the IRS, the Treasury inspector general for Tax Administration, and the Justice Department’s inspector general. His attorney Mark Lytle has also said that he has evidence that would contradict sworn testimony “by a senior political appointee,” which CBS has identified as Attorney General Merrick Garland.

Shapley has already faced political retaliation as has his whole team, according to his attorneys — they were all removed from the investigation at the request of the DOJ.

Sen. Ted Cruz’s Special Advisor for Communications, Steve Guest, pointed out that this contradicted what Garland had testified to when he was being questioned by Cruz back in March.

BOMBSHELL: IRS whistleblower says he witnessed interference by Biden's DOJ in the Hunter Biden criminal investigation.

REMINDER: This contradicts AG Garland’s claim the investigation was “not restricted…in any way.” when questioned by Sen. Ted Cruz.
pic.twitter.com/f4k0GuNLbG

— Steve Guest (@SteveGuest) May 25, 2023

WATCH: Sen. Cruz’s full line of questioning and AG Merrick Garland’s under oath testimony that is now contradicted by an IRS whistleblower. pic.twitter.com/qUAn52ggQj

— Steve Guest (@SteveGuest) May 25, 2023

Starting around 3:22:

Cruz: Will you commit that the investigation will actually examine the public corruption aspect and not simply scapegoat Hunter Biden as an individual?

Garland: I can’t comment about the investigation other than to say that all the matters involving Mr. Hunter Biden are in the purview of the US Attorney in Delaware. It’s not restricted in his investigation in any way.

Cruz: Well, you don’t comment here but then you leak at the same time.

That sounds like a direct contradiction of what Garland testified to, not to mention he would have to explain why the whole IRS team has been removed if that’s not “restricting” the investigation.

“When I saw the egregiousness of some of these things, it no longer became a choice for me,” he said. “It’s not something that I want to do. It’s something I feel like I have to do.”

He said his ultimate motivation is what drove him to pursue the work of criminal tax investigations in the first place.

“When taxpayers are treated differently — and subjects of investigations are treated differently,” he said, “I don’t see how it doesn’t affect the fairness of the system.”

So far, the DOJ isn’t talking. But we’ll likely hear more after Shapley testifies to the House on Friday. Hopefully, he will be protected for having the bravery to come forward and call out what was going on.