CNN  — 

Peter Navarro, an ex-White House aide to former President Donald Trump, has reported to a federal prison in Miami, making history as the first former White House official to be imprisoned for a contempt of Congress conviction.

Navarro was sentenced to four months in prison for his refusal to comply with a subpoena from the House Select Committee that investigated the January 6, 2021, US Capitol attack.

Before reporting to jail, Navarro spoke for 30 minutes at a gas station and called the case against him an “unprecedented assault on the constitutional separation of powers.”

He claimed that the legal tactics that were used against him would be used against Trump: “I am pissed – that’s what I am feeling right now.”

Navarro concluded: “God bless you all, see you on the other side.”

His conviction was a rare example of a member of Trump’s inner circle being held accountable by the criminal justice system for their resistance to scrutiny. Navarro’s stint in prison comes as Trump himself has yet to face criminal consequences for the various crimes he’s been accused of committing.

“It’s historic, and will be to future White House aides who get subpoenaed by Congress,” Stanley Brand, a former House general counsel who now represents Navarro as one of his defense lawyers, said on Monday.

Navarro’s punishment for evading a House probe will boost the leverage lawmakers will have – under administrations of both parties – to secure cooperation in their investigations.

For decades, the two branches of government have engaged in a game of chicken over the protections that surround the presidency and how Congress can enforce its subpoena; there have been incentives on both sides to negotiate towards a deal rather than test in court the monumental questions of executive privilege and immunity in court.

In this case, the Justice Department took the uncommon step of prosecuting a former White House adviser for blowing off a congressional subpoena, at Congress’ prompting after holding Navarro in criminal contempt and referring him to the Department of Justice. Prosecutors said Navarro’s whole-sale non-compliance with the lawmakers’ demands put him far afield from the back-and-forth other former officials typically have had with lawmakers over their participation in congressional probes.

Navarro made a last-ditch bid for a Supreme Court intervention that would put off his self-surrender to prison.

“The prosecution of a senior presidential advisor asserting executive privilege conflicts with the constitutional independence required by the doctrine of separation of powers,” his lawyers wrote to the high court. “Not once before Dr. Navarro’s prosecution has the Department of Justice concluded a senior presidential advisor may be prosecuted for contempt of congress following an assertion of executive privilege.”

His attorneys even invoked the mother of Supreme Court Justice Neil Gorsuch, Anne Gorsuch, who as Environmental Protection Agency administrator in the 1980s was held in contempt by the US House but never prosecuted.

Chief Justice John Roberts rejected Navarro’s request on Monday.

Navarro has never been able to show that executive privilege would have applied to the information he has related to the 2020 election.

US Solicitor General Elizabeth Prelogar countered to the justices that even “a successful claim of privilege would not excuse applicant’s total failure to comply with the subpoena.

While the US House many decades ago would apprehend on its own witnesses who thwarted their subpoenas, Congress in recent years could only seek subpoena enforcement through lawsuits – which became more difficult during the Trump presidency – and through Justice Department referrals. Yet the number of times the DOJ agreed to prosecute a witness for contempt of Congress are extremely low. In 2010, a political appointee in the George W. Bus​h administration was charged with contempt of Congress, then made a plea deal to serve one day in jail.

Blowing off the House January 6 probe

Though high-stakes showdowns over the participations of presidents and their advisers in congressional investigations predated the Trump administration, Trump and his allies took the resistance to a new level, both during and after the Trump presidency.

Navarro was subpoenaed for documents and testimony related to the efforts to overturn the 2020 election, culminating in the ransacking of the Capitol on January 6, 2021. Navarro rebuffed the demands, claiming that Trump had asserted privilege over the requests and arguing the House committee must negotiate with Trump directly to sort out that dispute. He was charged in June 2022 with two counts of contempt of Congress and was found guilty on both counts last September.

Former Trump adviser Steve Bannon was prosecuted and convicted on similar charges, stemming from his own non-compliance with a House January 6 committee subpoenas. He was no longer in the White House during the period the House committee was probing. The trial judge his case, US District Judge Carl Nichols, let Bannon delay serving his four-month prison sentence while his appeals continue to play out.

What Navarro’s incarceration could look like

“When I picked him up this morning, he was ready to go,” Sam Mangel, the prison consultant Navarro hired to prepare for his incarceration, told CNN’s Kaitlan Collins on “The Source” Tuesday night.

“I think this morning, he presented himself very well, very strong,” he said. “But naturally, anyone going to federal prison is going to be nervous. You lose all control. I don’t care who you are. I don’t care what your profile is. When you’re in there, you’re a number.”

Mangel also said that he’s since spoken with some of his other clients in the facility who have said Navarro’s “doing fine today.”

Navarro is expected to spend 90 days behind bars, given federal laws that allow for early release of certain inmates.

He was hoping to be assigned to an air-conditioned dormitory reserved for “elderly” male inmates, Mangel told CNN earlier.

That dormitory houses 80 men in bunk beds, he said, and there will be “no privacy in the dorm.”

“It can be scary and intimidating. But he’s going to be perfectly safe,” Mangel said. Navarro will have access to TVs that are set up in the prison and allow him to follow the news, and he will also be able to use email and make phone calls.

The prison is one of the older ones in the country, and it sits next to the city zoo.

“Not only can you hear the lions … you can hear the lions roar every morning,” Mangel said.

This story and headline have been updated with additional developments.

CNN’s Devan Cole and Jack Forrest contributed reporting to this story.