Given Cohen's prolonged time spent in proximity to Trump, his family and the Trump Organization, some insiders consider his cooperation with authorities to be one of most serious potential legal threats to confront the president.
Cohen said in a statement: "I look forward to having the privilege of being afforded a platform with which to give a full and credible account of the events which have transpired".
Cohen pleaded guilty in November for lying to Congress during private testimony in 2017 about the timing and extent of discussions he had about a Russian real estate deal during Trump's campaign. In the plea, Cohen said: "I made these misstatements to be consistent with Individual 1's political messaging and out of loyalty to Individual 1".
"I felt it was my duty to cover up his own dirty deeds", he told the judge during the sentencing hearing, referring to Mr Trump.
The lawyer has cooperated with Mueller's investigation into Russian interference in the election since a year ago, which has prompted anger from the president. It's unclear what Cohen will be allowed to talk about in the hearing and what Robert Mueller, or prosecutors in NY, will want him to keep to himself.
Based on the description in the court documents, Individual 1 appears to be President Trump.
The payments made or orchestrated to women during the campaign - to adult-film star Stormy Daniels and former Playboy model Karen McDougal - to stay silent about alleged sexual encounters with Trump are also sure to be a hot topic at the congressional hearing.
On the issue of possible collusion between the Trump campaign and Russia, Giuliani says, "Cohen doesn't know a damn thing about collusion".
The Democrats in the House have promised more oversight into the dealings of the Trump presidential campaign and administration, after investigations in the body over the role of Russian interference descended into partisan bickering during the first two years of Trump's term.
It's not yet clear whether Cohen will agree to speak to any other committees.
Cohen has testified behind close doors to both the Senate and the House previously, some of which led to his conviction on lying to Congress. Trump has denied having the extramarital affairs.
"Mr Cohen has expressed an interest in telling his personal story in open session, and we welcome his testimony before the Committee on Oversight and Reform", he said. House Judiciary Chairman Jerry Nadler of NY is demanding acting Attorney General Matt Whitaker testify this month, and he's threatening a subpoena if Whitaker won't voluntarily appear.