FIRST ON FOX: A man serving in prison for leaking President Donald Trump’s and thousands of others’ confidential tax records recently asserted his Fifth Amendment right to the House Judiciary Committee and declined to testify before the panel, Fox News Digital has learned.

A public defender wrote to the Republican-led committee on behalf of Charles Littlejohn, a former IRS contractor serving out a five-year sentence in Illinois, that because Littlejohn was appealing his sentence, he did not have to testify before Congress.

"The testimony that you seek from Mr. Littlejohn directly implicates his Fifth Amendment privilege against self-incrimination," the public defender wrote on Saturday. "Mr. Littlejohn validly exercises that Constitutional right in declining to testify."

EX-IRS CONTRACTOR WHO LEAKED TRUMP'S TAX RETURNS SENTENCED TO FIVE YEARS IN PRISON

The Republican-led House committee is investigating a plea deal Littlejohn reached with the Biden administration's Department of Justice (DOJ) in 2023. Littlejohn admitted to prosecutors as part of the plea bargain that he carried out an elaborate scheme to access and disclose Trump’s tax information and the tax returns of thousands of the wealthiest U.S. citizens to the New York Times and ProPublica. 

Among those targeted were Elon Musk, Jeff Bezos and Warren Buffett.

In return, Littlejohn was charged with and pleaded guilty to a single count of unauthorized disclosure of tax returns and received the maximum 60-month sentence for the charge.

At the time, U.S. District Judge Ana Reyes, an appointee of former President Joe Biden, questioned the wisdom of DOJ’s decision to charge Littlejohn with one charge when thousands had been affected by his actions, saying she was "perplexed" and "troubled" by the plea deal.

"The fact that he is facing one felony count, I have no words for," Reyes said during his sentencing hearing.

IRS LEAKER SOUGHT CONSULTANT ROLE WITH EXPRESS PURPOSE OF LEAKING TRUMP'S TAX RETURNS, DOJ SAYS

Many Republicans also piled onto the Biden DOJ for the perceived leniency of the plea agreement. Sen. Rick Scott (R-FL) said during the sentencing hearing it "makes no sense" and "should be called the plea deal of the century."

House Ways and Means Committee Chairman Jason Smith (R-MO) criticized prosecutors for failing "to deter future IRS employees from leaking sensitive taxpayer information."

House Judiciary Committee Chairman Jim Jordan (R-OH) wrote a letter Tuesday to the Trump administration's DOJ, obtained by Fox News Digital, requesting all communications and other records surrounding Littlejohn’s prosecution and accusing the prior administration’s DOJ of failing to provide "any substantive" information.

Jordan said he learned from the IRS that Littlejohn's breach was far more expansive than what had been established in court.

"After President Trump took office, the IRS disclosed to the Committee that over 405,000 taxpayers were victims of Mr. Littlejohn’s leaks and that ‘89 [percent] of the taxpayers [we]re business entities,'" Jordan wrote. "While it is now clear that Mr. Littlejohn’s conduct violated the privacy of hundreds of thousands of American taxpayers, it remains unclear why the Biden-Harris Justice Department chose to allow him to plead guilty to only a single felony count."

A DOJ spokesman declined to comment on Jordan’s request.

Following a recent terror attack in the heart of Boulder, Colorado, the county's GOP chair said local and state officials who enacted policies protecting individuals in the U.S. illegally are trading the law for tolerance.

Illegal Egyptian national Mohamed Sabry Soliman, 45, was arrested Sunday after allegedly throwing Molotov cocktails into a crowd of peaceful pro-Israel demonstrators near the Boulder County courthouse while yelling, "Free Palestine."

Authorities said eight people suffered burn injuries, and a total of 12 people were injured in the attack, which happened on the eve of Shavuot.

BOULDER TERROR ATTACK WITNESS DESCRIBES 'HORRIFIC' SCENE AT PRO-ISRAEL RALLY

"I find it interesting that with all of the things that have happened in Boulder, the one thing that's drawing out the most press and getting the most news is antisemitism," Boulder County Republicans Chairman Peg Cage told Fox News Digital. "Antisemitism is a big deal right now, and that person was guilty of that, and he admitted it himself. But if you look at what he did, it was when he was done with the United States."

Immigration authorities confirmed Soliman overstayed his non-immigrant visa, which was granted during the Biden administration.

WATCH: Boulder suspect throws incendiary device at pro-Israel supporters

BOULDER SUSPECT SPENT A YEAR PLANNING MOLOTOV COCKTAIL ATTACK ON PRO-ISRAEL MARCH: DOCS

He allegedly flew into Los Angeles International Airport on Aug. 27, 2022 with orders to return home by Feb. 26, 2023. However, he never left, filing a claim with U.S. Citizenship and Immigration Services just one month after his arrival in the country.

On March 29, 2023, Soliman was granted work authorization, which was valid through March of this year. 

"I mean, he waited until his daughter had graduated, and he had nothing to lose," Cage said. "He was here illegally, and then he committed the crime."

The attack took place near an event held by "Run for Their Lives," a worldwide grassroots organization that advocates for the release of Israeli hostages held since Oct. 7, 2023. The local Run for Their Lives chapter gathers in Boulder weekly.

Soliman, who authorities claim drove an hour to commit the act of terror, allegedly said after the attack "he would do it…again."

BOULDER TERROR ATTACK SUSPECT SAID HE WANTED TO KILL 'ALL ZIONIST PEOPLE,' USED MOLOTOV COCKTAILS: FEDS

"Frankly, if he hadn't been in the heart of Boulder, somebody probably would have shot him, because we're that way here," Cage said. "The reactions that I'm seeing, it rather confirms the America-first agenda of our president and of our Republican Party. … I think [crimes involving illegal immigrants are] just becoming more pronounced, and it's making us side more with our side."

Pointing to policies enacted by local and state officials, she questioned the disregard for immigration law in the name of tolerance.

"Basically, this wasn't a surprise as much [as], it's just like, thank God nobody got killed, and dang, why didn't somebody get him out of here when he first overstayed his visa," Cage said. "Why aren't we following our laws. … They're too tolerant, and they think it's a good thing."

She added that contradictions to President Donald Trump's directives are plainly visible on the Boulder County website and in public settings.

"If you go on to the Boulder County website, it's basically how to stay here if you're illegal," Cage said. "We had this Cinco de Mayo event, and the booth next to ours was how to avoid [Immigration and Customs Enforcement (ICE) and] how to report an upcoming ICE event that you might know about. … So, no, I'm not surprised. I'm disgusted. It needs to stop, and it makes that come clearer into focus."

MOHAMED SABRY SOLIMAN: WHAT WE KNOW ABOUT ILLEGAL IMMIGRANT ACCUSED IN COLORADO TERROR ATTACK

Soliman is charged with multiple counts of attempted first-degree murder, first-degree assault, possession of incendiary devices, and more than a dozen counts of attempted use of an incendiary device.

He is also facing federal charges for allegedly committing a hate crime involving actual or perceived race, religion or national origin.

The Boulder County commissioners and Boulder County Sheriff's Office did not immediately respond to Fox News Digital's requests for comment.