How fierce Trump ally Kash Patel could help reshape the FBI or Justice Department

Last year, as Donald Trump's reelection bid was underway, he declared that a new book by his fiercely loyal adviser Kash Patel would serve as a "blueprint" for his next administration.

"This is the roadmap to end the Deep State's reign," Trump said of the book on his Truth Social media platform.

Titled "Government Gangsters," it calls for a "comprehensive housecleaning" of the Justice Department and an eradication of "government tyranny" within the FBI by firing "the top ranks" and prosecuting "to the fullest extent of the law" anyone who "in any way abused their authority for political ends."

"[T]he FBI has become so thoroughly compromised that it will remain a threat to the people unless drastic measures are taken," Patel claimed in his book. Democrats "should be very afraid," Patel wrote, as Trump and his allies battle "the Deep State" -- what conspiracy theorists claim is a cadre of career employees inside government who are working together to secretly manipulate policy and undermine elected leaders.

After Trump's historic reelection last week, media speculation has suggested that Patel, a former Defense Department official, could be under consideration to become Trump's attorney general or CIA director -- or that he could even replace current FBI Director Christopher Wray, who Trump has reportedly vowed to fire.

"President Trump called [my book] the roadmap for 2024, and now let's put it into work," Patel said Thursday on a podcast, without indicating whether he himself might take on a senior-level role in the incoming administration.

A spokesperson for Trump's transition team did not respond to a request for comment from ABC News.

Patel's proximity to Trump and Trump's public embrace of Patel's book underscore how a major shake-up could be coming to the Justice Department or FBI.

Here is what Patel has said about what new leadership could do.

Fire and potentially charge FBI and DOJ officials

Patel, who once served as a prosecutor in the Justice Department's National Security division, has long accused leaders in the FBI and Justice Department of exploiting their authority to boost Democrats and undermine Republicans -- especially Trump.

There's been a "two-tier system of justice," Patel has routinely said.

He often highlights his subsequent work as a congressional investigator, when he helped lead the House Republicans' probe of "Russiagate" -- which, as he describes it, exposed FBI wrongdoing in its 2016 investigation of alleged ties between Trump's presidential campaign and Russia.

That work led to Patel joining the Trump administration in 2019, and in the final year of Trump's presidency, Patel was appointed acting deputy director of national intelligence -- the second-in-command of the entire U.S. intelligence community -- and then chief of staff to the acting U.S. defense secretary, a position critics claimed he was unqualified to hold.

A special counsel investigation launched by the Justice Department under Trump's first term concluded that "senior FBI personnel" and federal prosecutors working the Russia-related probe had "displayed a serious lack of analytical rigor" toward politically-tainted information, failing to "adequately examine or question" that information before launching a full-scale investigation of Trump and his associates, which included intercepting the communications of one former Trump adviser.

In its own report on the matter, the office of the Justice Department's inspector general said that while it found "fundamental errors" and significant "failures" in the FBI probe, it found no evidence that "political bias or improper motivation influenced" the investigation, including the decision to intercept those communications.

Still, in his book, Patel said "all those who manipulated evidence [or] hid exculpatory information" should face charges.

He also alleged "abuses of prosecutorial discretion" by the Justice Department in declining to charge Hillary Clinton for allegedly compromising classified information through her use of a private email server, and in declining to charge President Joe Biden's son, Hunter Biden, for what Patel describes as influence-peddling -- while indicting Trump ally Steve Bannon over his refusal to comply with a subpoena from the House panel investigating the Jan. 6, 2021, attack on the U.S. Capitol and also charging so many of the Trump supporters who were at the Capitol that day.

"Those specific prosecutors, and division[s] within the department, that selectively apply the law should be removed and brought to heel," Patel wrote in his book.

In a campaign video released last year, Trump promised that if reelected, he will "immediately reissue" a 2020 executive order giving him the power "to remove rogue bureaucrats."

"And I will wield that power very aggressively," he declared.

Trump also said he will "totally reform" the court system that in 2016 and 2017 approved the FBI's applications to intercept his former adviser's communications.

Strip 'massive' amounts of security clearances

On another podcast two months ago, Patel said anyone involved in "Russiagate" should be stripped of their security clearances.

According to Patel, there is a "massive" list of such government officials, from the FBI and Justice Department to the CIA and U.S. military.

"They all still have clearances," including those who left government for private sector jobs, so "everybody" should lose their clearances, Patel said.

Patel said he has personally "recommended" to Trump that the new administration also strip any security clearances still held by the 51 then-former intelligence officials, including former Director of National Intelligence James Clapper and former CIA director John Brennan, who in October 2020, just weeks before the 2020 presidential election, signed onto a letter dismissing the public release of emails from Hunter Biden's laptop as part of a "Russian information operation."

"We want to emphasize that we do not know if the emails ... are genuine or not and that we do not have evidence of Russian involvement," they wrote. "[But if] we are right, this is Russia trying to influence how Americans vote in this election, and we believe strongly that Americans need to be aware of this."

Trump and his allies have accused the 51 former intelligence officials of trying to influence the 2020 election themselves. And that's why Patel wants Trump to strip them of their clearances.

"Because it's justified," Patel said. "It's not an act of vengeance. They have had the opportunity to recant, and all 51 of them have doubled-down, and tripled-down. So pull them. I think he will."

'Close down' FBI headquarters

Speaking on Thursday's podcast about FBI headquarters in Washington, D.C. -- where more than 7,000 agents, analysts, administrative personnel and other employees work -- Patel said that the new Trump administration should "close that building down."

"Open it up the next day as the museum to the Deep State," he added.

Patel said the FBI should then leave about 50 people from its staff somewhere in Washington to help keep the agency running, and send the thousands of other employees into the field to join the 16,000 employees already there.

Meanwhile, in his book, Patel said the Justice Department should "drastically curb" the number of cases that it prosecutes in Washington, because Washington is "perhaps the most liberal jurisdiction in America."

Release still-secret documents

On Thursday's podcast, Patel described Trump's election victory as a "mandate for the truth" about "the corruption" inside government.

Therefore, he said, the new Trump administration should "get out all the remaining documents that were blocked" by the Biden administration and by "Deep State" efforts in other administrations.

Patel has long called for the public disclosure of documents still unreleased from the FBI's investigation of Trump and alleged ties to Russia.

On Jan. 19, 2021, Trump's final full day in office, the outgoing president announced that he had declassified a binder with many of those documents. But for reasons that still remain unclear, none of the documents were ever officially released.

Now, as president again, Trump "can expose the documents that these folks have written for decades, allowing [their] corrupt activities," Patel said on Thursday.

"He's going to come in there and maybe give them the Epstein list, and maybe the P. Diddy list," Patel added, referring to documents involving the late sex-offender Jeffrey Epstein and hip hop mogul Sean "Diddy" Combs, who denies wrongdoing in the sexual abuse cases recently filed against him and maintains his innocence on the criminal charges he faces.

In the campaign video released last year, Trump promised to establish a "Truth and Reconciliation Commission" that will "declassify and publish all documents on Deep State spying, censorship, and corruption."

It's all part of "my plan to dismantle the Deep State and reclaim our democracy from Washington corruption once and for all," he said.