U.S. President Donald Trump's former personal lawyer Michael Cohen is planning Wednesday to pull back the curtain on his ex-boss's alleged criminal conduct. Now, all Cohen needs to do is convince Americans he's telling the truth.

Cohen, a convicted felon who has already pleaded guilty to lying to Congress, testifies at 10 a.m. ET, with the cameras rolling and expectations running high that he will accuse the president of engaging in criminal activity while in office. It will be his second of three back-to-back meetings on Capitol Hill, and the only hearing that will be broadcast.

Cohen was Trump's personal attorney for years and has worked for the president for more than a decade as his fixer. On Wednesday, Cohen will reportedly discuss Trump's alleged use of racist language, and will testify that the president lied about his net worth to evade taxes.

"Michael Cohen appears to have decided he just wants to totally come clean and be transparent and tell the entire world what he knows, regardless of any tangible benefit he might get from the government," said Greg Brower, former head of the FBI's Office of Congressional Affairs. "That's a huge problem for the president, potentially."

Here are some key considerations as Cohen prepares to testify:

Cohen might have the goods on financial cheating

Cohen arrives at the Hart Senate Office Building before testifying to the Senate Intelligence Committee on Capitol Hill on Tuesday in Washington, D.C. He testifies again Wednesday in a public hearing. (Mark Wilson/Getty Images)

Cohen knows a lot about Trump and his business dealings throughout the last decade. "He knows where the proverbial bodies are buried," as Brower says.

That puts Cohen in a position to paint a damning portrait of Trump, the private businessman. The Wall Street Journal reports that Cohen "will make public some of Mr. Trump's private financial statements," and tell Congress that Trump inflated or deflated his net worth to dodge taxes.

The House Committee on Oversight and Reform is expected Wednesday to ask Cohen about matters such as potential corrupt practices in contracting for Trump towers overseas, potential violations of the Foreign Corrupt Practices Act or about his knowledge of whether Trump has paid property taxes.

Don't expect big insights on Russia probe

Cohen is one of a few people who can explain the timeline for negotiations to build a Trump Tower Moscow, and whether the president may have directed him to lie to Congress last year when he said the real-estate negotiations ended in January 2016. (Cohen now admits the discussions continued well into Trump's presidential campaign.)

The former Trump lawyer could also be asked about how much if any direction Trump gave in making contacts with Russians.

However, Wednesday's televised testimony will reportedly steer clear of U.S. Special Counsel Robert Mueller's investigation into Russian meddling in the 2016 presidential election. That means the topic of the Trump Tower Moscow timeline should be off the table.

Lawmakers will grill Cohen on campaign funds

Trump and Cohen in better times, during an election campaign stop at the New Spirit Revival Center church in Cleveland Heights, Ohio, in September 2016. (Jonathan Ernst/Reuters)

Cohen plans to talk about potential criminal activity relating to hush-money payments he facilitated to the pornographic film actress Stormy Daniels and the former Playboy model Karen McDougal, in order to silence both of them about alleged extramarital affairs with Trump.

Cohen has admitted he broke campaign finance laws.

Federal investigators are also investigating the Trump inaugural fund and whether the 2017 inaugural committee received illegal foreign donations by people from Middle Eastern nations. A ProPublica/WNYC investigation found that the inaugural committee paid more than the going rate for venue rental in the Trump Hotel in Washington, D.C., potentially violating tax law while profiting the president.

"If [Cohen] has got information to give, particularly about the money that flowed into the inauguration, then hearing a detailed description of what happened there from his point of view, and whether that violates any federal election law, would be interesting," Michael Zeldin, a former assistant to Mueller, said in an interview.

Pay attention to dates

Listen on Wednesday for precise dates of when alleged crimes were committed. The calendar will matter to prosecutors, as far as whether the five-year statute of limitations for many of the relevant federal crimes may have run out.

A crime has to be indicted within five years, or it's as if it never happened. Under Department of Justice guidelines, a sitting president cannot be indicted. But Trump was inaugurated on Jan. 20, 2017, meaning he could be liable to criminal exposure if he fails to win re-election in 2020.

So it might stand to reason that Trump would have good incentive to run for a second term in 2020 and win in order to avoid possible prosecution. If he can stay in office until 2024, he can outlast the statute of limitations.

All of which is to say what happened between January 2016 and today will be of a lot more interest to prosecutors than what happened before that same time period.

Cohen's credibility on trial

Washington reporter Keith Boag takes an in-depth look at the Mueller investigation evidence and what we know so far. Correction: An on-screen graphic in this video indicates James Comey was fired on May 9, 2016. He was, in fact, fired on that date in 2017. 12:35

What good is Cohen's word in a sworn testimony before Congress? He has, after all, pleaded guilty to lying to the House and Senate intelligence committees in 2017, and will serve time for it beginning in May. Whatever Cohen tells legislators Wednesday, then, won't count for much without corroboration.

"It's like this rock 'n' roll song … where the refrain is, 'Can we corroborate? Can we corroborate?'" Zeldin said. "Everything has to be corroborated because as a bald witness — meaning Cohen, alone — he has a credibility problem."

Cohen was sentenced to three years in December. He does not have a co-operation agreement with the U.S. District Court for the Southern District of New York (SDNY).

William Yeomans, a fellow in law and government at American University, said that while Cohen "undoubtedly has devastating information" about Trump, selling himself as honest will be his biggest challenge as Republicans will try to undercut his credibility.

"A segment of the public will not accept Cohen's testimony, no matter how credible," he said. "Cohen's testimony should help define how large that segment is."

Cohen has much to gain

The prospect of a lighter prison sentence will have important bearing on who Cohen's audience is when he speaks.

So Cohen's target audience is narrow, said former federal prosecutor Julie Grohovsky. He needs to fall back into the good graces of the SDNY, which can file a "Rule 35" motion for him under the Federal Rules of Criminal Procedure.

The SDNY's office previously recommended a "substantial term of imprisonment" of up to 63 months for Cohen, citing his decision "not to pursue full co-operation." Cohen now has another chance to make things right within one year of his sentencing, and convince prosecutors to request leniency in court.

Legal scholars say Cohen has likely already sought SDNY's blessing before testifying. But there's a possibility prosecutors will learn something new from him on Wednesday.

"If he's bringing forward things in this hearing that are topics prosecutors are interested in, he has a chance of getting this Rule 35 motion and getting a [sentence] reduction," Grohovsky said. "So while he cares what the general public thinks, he cares very much that prosecutors want to talk with him some more."

Brace for theatrics

Trump has already been accused of witness tampering, after he tweeted ominously to "watch" Cohen's father-in-law. Last month, Cohen withdrew his commitment to testify, with his lawyer citing "threats against this family" by the president. On the eve of Cohen's Wednesday testimony, Republican congressman Matt Gaetz of Florida also tweeted a warning, hinting at disclosures about Cohen's "girlfriends" to his wife.

A screenshot of Gaetz's tweet on Tuesday that the Florida state bar is now investigating. The tweet has since been deleted. (CBC)

Cohen is expected to testify about the intimidation on Wednesday. He will also reportedly tell lawmakers about alleged racist statements the president has made in his presence, a potential revelation that wouldn't so much have any legal implications as it would further damage Trump's character.

"If Michael Cohen says, 'Yes, I heard the president use the N-word in my presence numerous times, and I have recording after recording of that, and I'm going to share them on the internet for all the world to hear,' well, that's not a crime," Zeldin said. "That's theatre. And people will do with it as they want."

Impugning the president's character isn't really a legal matter, but it is salacious. A number of House progressives on the panel, including Rashida Tlaib and Alexandria Ocasio-Cortez, will get a chance to grill Cohen before live TV cameras.

Testimony that embarrasses the president is one thing; testimony that suggests criminal liability is quite another, and it will demand corroboration, said Mark Osler, a criminal law scholar and expert on sentencing.

"There's no doubt there's a political element to this whole thing," he said. "One thing that we can certainly hope for is that members of the committee will use this as an opportunity to ask questions as opposed to make speeches because there are legitimate questions that should be asked."