For the next two days, Congress will hold hearings on claims that Trump sought to shut down the Russia investigation

The investigation into Russian interference in the 2016 election is entering a high-stakes phase for the White House as lawmakers prepare to publicly question former FBI Director James B. Comey and other top intelligence and law enforcement officials about whether President Trump sought to block the FBI inquiry.

The Senate Intelligence Committee will hold hearings on Wednesday and Thursday into the intensifying legal and political thicket, one that already has spawned a special counsel to oversee a multi-pronged FBI investigation, a related criminal grand jury inquiry and four separate congressional investigations.

Comey’s testimony on Thursday will be the marquee event, broadcast live on nearly every TV network and cable news channel, since the former FBI director will be speaking out for the first time since Trump fired him without warning on May 9 for what the president later described as the “Russia thing.”

Whatever light they may shed, the political theater of nationally televised hearings will be a reminder of previous congressional nail-biters — especially Watergate in the 1970s, Iran-Contra in the 1980s and Monica Lewinsky in the 1990s — that riveted the nation and brought down or sharply undermined Presidents Nixon, Reagan and Clinton.

The political risks may be just as high for Trump, who has been forced to retain his own lawyer for the Russia-related inquiries as he struggles to take control of a sprawling political agenda and a skeptical Republican Party less than five months after taking office.

Lawmakers said Tuesday that they expect Comey to provide details about his phone calls and meetings with Trump but to refrain from discussing the FBI investigation into any Trump campaign ties to Russia. It’s not clear how far Comey will go in public in laying out his legal concerns about Trump’s comments.

If he comes close to affirming in public the same level of concern that associates have said he expressed in private, it will be an explosive hearing that could further cloud Trump’s White House with questions of whether he sought to obstruct justice, a potentially impeachable offense.

“If he confirms what’s been alleged, it’s obviously serious business,” Rep. Adam B. Schiff of Burbank, the top Democrat on the House Intelligence Committee, said in an interview.

He added, “I don’t think we ought to anticipate the consequences until we get all the facts.”

Comey is likely to face withering questioning from some Republicans intent on defending the president and poking holes in Comey’s interpretation of his conversations with Trump.

“If he has the view that he can talk about specific things he wants to talk about and can’t talk about exactly similar things that he doesn’t want to talk about, I think that’ll be a big problem with me — and with the committee,” said Sen. Roy Blunt (R-Mo.), a committee member who is part of the GOP leadership.

Comey also is likely to be asked about a New York Times report that during a dinner in January, the president asked Comey to pledge loyalty to him. Comey declined to do so, he later told associates.

Before a White House meeting with congressional leaders Tuesday, Trump was asked if he had a message for Comey. “I wish him good luck,” the president said.

The hearings kick off Wednesday when some of America’s top national security officials — Dan Coats, the director of national intelligence; Adm. Michael S. Rogers, director of the National Security Agency; Andrew McCabe, acting FBI director; and Rod Rosenstein, the deputy attorney general — will testify.

Lawmakers are likely to press the intelligence officials about the leak of a classified report on Russian hacking to the Intercept, a national security news website. Federal prosecutors filed a criminal complaint against a government contractor in Georgia, charging her with sharing classified information with a news organization.

In a House hearing last month, Coats and Rogers refused to discuss reports that Trump also had sought to pressure them to ease up on the Russia inquiry. Both said they would not discuss their private conversations with the president.

But Comey insisted on testifying in public, raising the likelihood that he will provide an account of his private meetings and calls with Trump.

Before he was fired, Comey’s associates have said, he had carefully rebuffed what he interpreted as requests from Trump to stop the FBI investigation of former White House national security advisor Michael Flynn, who was forced to resign in February after officials said he had lied about his conversations with the Russian ambassador.

On Tuesday, Flynn turned over 600 pages of business records to the Senate Intelligence Committee, complying with a subpoena seeking documents from his consulting business related to Russia, according to a congressional aide.

Comey apparently cleared what he planned to tell Congress when he spoke last week with Robert S. Mueller III, the special counsel appointed by the Justice Department to oversee the federal investigation.

“I understand the Special Counsel has not fenced him off in any way, shape or form,” Sen. Richard M. Burr (R-N.C.), chairman of the Senate Intelligence Committee, told CNN.

The House Intelligence Committee is conducting a separate inquiry into Russia’s role in the election and has asked Mueller to see Comey’s memos of his conversations with Trump. “We have an aggressive investigation going on right now,” Rep. K. Michael Conaway (R-Texas), who is leading that inquiry, said Tuesday.

The Senate hearing Thursday is expected to focus, in large part, on those memos.

Trump told Comey on Feb. 14, the day after Trump fired Flynn, that “I hope you can see your way clear to letting this go,” referring to the FBI’s Flynn investigation, according to an associate of Comey who has read the memo the FBI director wrote after the meeting. “He is a good guy,” Trump said of Flynn.

Comey wrote other memos to document other Trump statements that he found potentially improper, the associate said. He has not given copies of the memos to the committee, apparently because they are considered potential evidence in the FBI investigation, two congressional aides said.

When he fired Comey, Trump declared in a statement that Comey had told him three separate times that he was not under FBI investigation.

The next day, Trump derided the FBI director as “crazy, a nut job” to Russia’s foreign minister and its ambassador during a private meeting in the Oval Office, according to published reports that cited a leaked White House transcript.

After stories described Comey’s memos of his conversations with Trump, the president said on Twitter that the ousted FBI director had better hope that no secret “tapes” existed of their discussions, an implied threat that added echoes of Watergate to the drama.

Trump and his aides have denied any wrongdoing, arguing that the leaks of classified material to the media have posed a greater threat to national security than Russian meddling in the election.

Although nearly a month has passed since he fired Comey, Trump has yet to name a new FBI director. The president has scheduled a speech to religious conservatives on Thursday shortly after Comey is expected to begin his testimony.

Times staff writer Lisa Mascaro contributed to this story.

david.cloud@latimes.com

Twitter: @davidcloudLAT

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