The testimony on Wednesday from Michael Cohen, President Trump's former personal lawyer who's headed to federal prison in early May, was a potentially seminal moment in the myriad investigations into the Trump administration House Democrats are expected to launch now that they control the chamber. It also provided a window into the real estate developer's surprise rise to the presidency in 2016 from the perspective of a top lieutenant who was by Trump's side for a decade.

Cohen, at one time one of Trump's closest advisers and a self-described "fixer," used his public testimony before the House oversight committee to detail the lengths he went to in order to protect Trump — and his 2016 presidential campaign — from potential scandals as well as to help inflate estimates of Trump's personal net worth.

Cohen also came armed with literal receipts in the form of the image of a March 2017 payment Trump made to him while in the White House from a blind trust Trump claimed was set up to separate his business interests from his duties as president and the image of a second check from August 2017 check baring Trump's distinctive signature which together instead showed he was very much still involved in the family-run business.

Republicans used the hearing to try to undercut Cohen, who has pleaded guilty to lying to Congress and will soon begin serving a three-year prison sentence. While Cohen tried to show he was a changed man who regretted protecting Trump — who he branded a "racist," "con man" and "cheat" in his testimony — GOP lawmakers argued that Cohen was more interested in a rebuilding his image and setting himself up for financial profit post-incarceration.

Here are five major revelations from the Cohen's testimony before the House oversight committee:

(1) California Democrat: "Garden variety financial fraud"

Cohen was famously at the center of arranging a payment related to Trump's alleged sexual encounter with adult film star Stormy Daniels, who was paid $130,000 to keep quiet about a claimed 2006 tryst. Trump has denied Daniels' allegation that the two ever had a sexual relationship. Under an agreement between Trump and Cohen, the attorney would pay Daniels and then be reimbursed.

But that repayment didn't come immediately — and Cohen showed that it stretched into Trump's time in the Oval Office in 2017. Instead of paying in a lump sum, smaller payments were used to make it look like Cohen was simply being paid a legal retainer. One check he showed lawmakers was for $35,000 and was dated August 1, 2017 — signed by Trump well into his first year in office. Another, dated March 17, 2017, was signed by Trump Organization CFO Allen Weisselberg and Donald Trump Jr., the president's eldest son.

But the source of the March 2017 check's funds was perhaps the most interesting — coming from the trust Trump had set up before entering the White House to relinquish control of his business interests. The two payments when considered together, however, appear to offer verifiable proof Trump was still very much involved.

During his questioning of Cohen, Rep. Ro Khanna, D-Calif., said the proof of payments Cohen had brought to lawmakers suggested "garden variety financial fraud."

"Are you telling us, Mr. Cohen, that the president directed transactions in conspiracy with Allen Weisselberg and his son Donald Trump Jr. as part of a criminal conspiracy of financial fraud. Is that your testimony today?," Khanna asked.

"Yes," Cohen replied, seeming to suggest this could be something that federal prosecutors in Manhattan are also probing.

House oversight committee Chairman Elijah Cummings, D-Md., appeared convinced. After the hearing, reporters asked if he believed Trump had committed a crime while in office, given the check Cohen produced. "It appears that he did," Cummings responded.

(2) Concerns about other allegations after Access Hollywood tape

Cohen also testified that the reason Trump was worried about Daniels' allegations and those of another woman possibly coming to light was because of the damaging Access Hollywood video that surfaced at the beginning of October 2016 where Trump was caught on tape a decade prior discussing groping, grabbing and kissing women without their permission.

Trump has claimed the payment to Daniels had no connection to his 2016 presidential campaign and that it was simply made for personal reasons to do away with untrue allegations. But as Cohen told Del. Eleanor Holmes Norton, D-D.C., Wednesday, he was instructed to facilitate the payments to both women because Trump was worried about a "wildfire" effect after the 2005 interview with Billy Bush surfaced.

"He was concerned with the effect that it had on the campaign and how women were seeing him and ultimately if he would have a shot in the general election," Cohen said.

Cohen added that Daniels' then-attorney said the adult film actress wanted $130,00, and Trump told Cohen to " 'go ahead and do it.' "

Cohen also detailed to Rep. Robin Kelly, D-Ill., the surreptitious way that was devised to dole out the payments through an LLC so that Melania Trump wouldn't discover them, and then Cohen used a personal home equity line of credit so that the payments both couldn't be traced back to Trump and so none of it would raise an eyebrow with Cohen's wife, who handles the couple's finances.

As for being repaid, Cohen detailed how that was set up as well.

"I obviously wanted the money [back] in one shot. But in order to be able to put it onto the books, Allen Weisselberg made the decision that it should be paid in 12 months so it would look like a retainer," Cohen said, adding that "everything had to go through Mr. Trump and it had to be approved by Mr. Trump."

(3) A "treasure trove" of allegations after years of "catch-and-kill"

That wasn't the only questionable work Cohen did for Trump, though. He also laid out how he worked, in conjunction with David Pecker, the CEO of American Media Inc. (AMI) which publishes the National Enquirer, to "catch and kill" potentially damaging stories about Trump — by paying sources for exclusive rights to their stories and then never publishing those stories.

The practice went beyond paying former Playboy model Karen McDougal, who has also claimed she had an affair with Trump and was paid $150,000 by AMI shortly after Trump won the GOP nomination in 2016. Trump has denied McDougal's allegations of an extramarital affair.

There were other unverified stories that Pecker, a Trump ally, worked to bury such as a possible Trump love child and a rumored video tape of a fight between Melania Trump and the future president in an elevator, both of which Cohen said were untrue.

Still, Cohen said the Trumps were very worried about the "treasure trove of documents" Pecker had accumulated over the years that predated even Cohen's time working for the president.

The former Trump attorney's statements on the practice of "catch-and-kill" suggested there could be plenty of possible dirty laundry under wraps in AMI's possession that could be ripe fodder for 2020 opposition research, or investigative leads for Justice Department special counsel Robert Mueller, or grounds for a potential impeachment case against the president, or even compromising material that Russia or another hostile power could use against Trump if it were ever to be released.

(4) Ocasio-Cortez lays groundwork to seek more info on Trump finances

Questioning by Freshman Rep. Alexandria Ocasio-Cortez, D-N.Y., was among the most anticipated of the hearing. The rising Democratic star didn't grandstand. Rather, she used her time to appear to make a case for subpoenaing Trump's tax returns at a later date by asking Cohen for names of other associates who were witness to Trump's efforts to inflate his personal wealth for insurance purposes while also seeking to decrease it to avoid paying property taxes on several properties.

"To your knowledge, did the president ever provide inflated assets to an insurance company?" she asked. "Yes," Cohen replied. "Who else knows that the president did this?" Ocasio-Cortez continued. "Allen Weisselberg, Ron Lieberman and Matthew Calamari," Cohen said, referring to several Trump associates. And she also asked about Trump trying to reduce local tax bills by then deflating the value of his assets, pointing to one of his golf courses in her district which has been the subject of such reports.

"You deflate the value of the asset and then you put in a request to the tax department for a deduction," Cohen explained.

(5) Show him the money?

Many Republicans at Wednesday's hearing used their allotted time to probe Cohen's motives for shifting his loyalty away from Trump after years of dedicated service — and the financial gain Cohen could potentially reap from telling his story.

Cohen repeatedly stressed all he had lost through actions he'd taken and choices he made during 10 years working as Trump's personal attorney — not just the jail time he's facing, but fearing for his family's safety, losing his business and now being disbarred.

"I don't expect I'm going to have a source of income when I'm in federal penitentiary," Cohen said.

However, he did admit to Rep. Virginia Foxx, R-N.C., that he has been approached about possible TV, movie or book deals — which he wouldn't rule out accepting at some later point.

"So you don't commit to changing your ways, basically? Because you want to continue to use your background as a liar, a cheater, a convicted liar, to make money?" Foxx asked.

Expect Republicans to use that answer repeatedly as they continue to highlight questions about Cohen's credibility and motives.

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