Updated at 7:50 a.m. ET

Michael Cohen is poised to take a historic shot at his onetime boss and patron on Wednesday, claiming in prepared testimony that President Trump is a “racist” and “conman” who knew that an associate was in contact with WikiLeaks about their releases of Democratic emails during the 2016 campaign.

Cohen, President Trump’s former personal lawyer, is scheduled to appear before the House oversight committee on the second of his three days of meetings with lawmakers this week. The session is the only one that will take place in public, and Republican lawmakers are prepared to respond to Cohen with numerous questions about his credibility.

In prepared remarks obtained by NPR, Cohen is expected to make a series of bombshell accusations about Trump’s character, his business dealings, his 2016 presidential campaign, and an ultimately unsuccessful venture involving a Trump Tower project in Russia.

Cohen is expected to bring several documents, including copies of checks and financial statements that he says support his testimony, as he attempts to overcome questions about the veracity of his testimony since he pleaded guilty last year for lying to Congress.

The president’s former personal lawyer plans to say that Trump knew that his associate Roger Stone was talking to WikiLeaks about a coming release of hacked Democratic National Committee emails, and was aware ahead of time that the DNC emails would be released.

Cohen will say in his opening remarks that he does not have direct evidence that Trump or anyone in his campaign actively conspired with Russia to influence the presidential campaign, saying just that he has “suspicions.”

As a former Trump employee, Cohen said that during the 2016 campaign he helped Trump direct negotiations for a Trump Tower in Moscow, and that Trump was behind the project.

“To be clear: Mr. Trump knew of and directed the Trump Moscow negotiations throughout the campaign and lied about it,” Cohen’s prepared testimony reads.

Cohen goes into great detail about the payments made to adult film star Stormy Daniels in exchange for her silence about an alleged affair with Trump before he was president.

Cohen will say that Trump signed a personal check to reimburse him for hush money while in office — money that Cohen later pleaded guilty to campaign finance violations for.

Cohen says that Trump signed the check in August 2017, well after the president’s inauguration, as part of a “criminal scheme.”

Cohen is also expected to deliver a scathing testimonial about Trump’s personal character.

“Mr. Trump is an enigma. He is complicated, as am I. He has both good and bad, as do we all. But the bad far outweighs the good, and since taking office, he has become the worst version of himself,” Cohen’s prepared testimony states. “He is capable of behaving kindly, but he is not kind. He is capable of committing acts of generosity, but he is not generous. He is capable of being loyal, but he is fundamentally disloyal.”

President Trump responded overnight from Vietnam, where he’s meeting with North Korean leader Kim Jong Un. In a tweet, Trump said that Cohen “did bad things unrelated to Trump.”

The highly anticipated hearing is expected to dominate the airwaves and could bring portions of America to a standstill just as in the summer of 2017, when former FBI Director James Comey appeared before the Senate intelligence committee.

Then, as now, the witness had a story that could have been politically damaging for Trump. Then, as now, Trump’s allies sought to undercut that story with attacks both on it and the man telling it.

But that may be where the similarities end.

Cohen’s hearing, for example, will not take place in the collegial, typically more bipartisan Senate but in the often raucous and bare-knuckle House. And Cohen isn’t supposed to address the Russian interference in the 2016 presidential election, as he did behind closed doors on Tuesday with the Senate intelligence committee.

Precisely what Cohen told senators in that session remains unclear.

But Cohen and members of Congress on Wednesday are supposed to confine themselves to other wrongdoing that involved him and, allegedly, Trump. In fact, a person familiar with Cohen’s preparations said on Tuesday that Cohen intends to present evidence of wrongdoing by Trump that has taken place since his inauguration, although it isn’t clear what.

The White House dismissed whatever allegations Cohen may make in a pre-buttal Tuesday that noted he is a “disgraced felon” and “convicted liar.” The administration also lamented that the House oversight committee has “given [him] yet another opportunity to spread his lies.”

That won’t stop Trump himself from watching. Although the president is in Vietnam for his summit with North Korean leader Kim Jong Un, Trump intends to stay up all night in his time zone to watch, according to CNN.

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Battle over Cohen’s word

Cohen’s credibility is expected to be a central point of the back-and-forth on Wednesday. He has pleaded guilty to lying to Congress before and may have been involved in even more allegedly illegal or improper activity than he has admitted.

Republicans are expected to try to undermine Cohen’s statements by underscoring his admissions in his federal criminal cases and, perhaps, to bring in other material they have assembled in preparing for the hearing.

Rep. Matt Gaetz, R-Fla., opened the bidding on Tuesday afternoon with a post on Twitter that could set the tone for the balance of Cohen’s proceedings. (Gaetz, a Trump ally, does not sit on any of the three committees Cohen is appearing before this week but is a member of the House Judiciary Committee, which conducted several hearings that touched on the Justice Department’s Russia investigation when the committee was led by Republicans during the previous session of Congress.)

And the oversight committee’s top Republican, Rep. Jim Jordan of Ohio, suggested earlier that the panel’s minority might not feel bound by the ground rules set by Chairman Elijah Cummings, D-Md.

Jordan and his fellow Republicans might want to ask Cohen, for example, about the Russia investigation, expecting that his answers might be more helpful to them than to Democrats.

The degree to which he engages could be suggestive about which branch of the many storylines in the Trump saga — the 2016 negotiations over a skyscraper in Moscow, for example — may be connected to the question about whether anyone in Trump’s 2016 campaign conspired with the Russian attack on the election.

At least one answer helps Republicans politically: Cohen has rejected the account given about him in the infamous, partly unverified Russia dossier, which helps Republicans present that dossier as false and, more broadly, to present the whole Russia investigation as a hoax.

One question for Jordan and the oversight committee’s GOP minority on Wednesday will be how much to try to destroy Cohen’s word if accepting it in some instances, as with the dossier travel story, helps defend Trump.

Many of Trump’s opponents, meanwhile, don’t believe Cohen’s denials about the dossier. That may entice them to play by Cummings’ rules, especially if whatever information and allegations Cohen intends to lay before the committee are new and interesting enough to break through with a national audience.

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