Numerous lawsuits and investigations into his affairs are being carried out by Democratic-led congressional committees and by prosecutors in New York.
By far the most serious is the announcement on Tuesday, September 24, by Nancy Pelosi, the Democratic speaker of the House of Representatives, that the body is opening a formal impeachment inquiry into Trump over the Ukrainian scandal.
Here is a list of some of the legal woes facing the US president:
New York prosecutors have been probing illegal payoffs made by Michael Cohen, Trump's former personal attorney, to buy the silence of at least two women, Stormy Daniels and Karen McDougal, who claimed to have had affairs with Trump before he ran for president.
Cohen, who is currently serving a three-year prison term, is potentially a dangerous witness for Trump as a longtime insider who has turned against his former boss.
The hush payments were part of a "catch-and-kill" arrangement with the National Enquirer tabloid, which, according to Cohen, had a financial arrangement to protect Trump from damaging personal news.
Cohen testified that the payment he made to Daniels, which was ruled an illegal use of campaign funds, was ordered and reimbursed by Trump himself – a possible criminal act.
In his February testimony in Congress, Cohen raised issues of financial malfeasance by Trump and the Trump Organization in banking and real estate deals.
Cohen said Trump falsified data in financial disclosures to banks and insurance companies, providing more meat for federal investigators.
For that, eyes have been on the figure who likely knows more secrets about Trump than anyone else: Allen Weisselberg, the accountant who has served the Trump Organization for 4 decades.
The Trump Foundation, the former charitable arm of the Trump Organization, is the target of a lawsuit brought by the New York state attorney general.
The Trump Foundation agreed to shut down in December after the attorney general accused it of engaging in a "shocking pattern of illegality."
Former New York attorney general Barbara Underwood said the Trump Foundation was involved in "unlawful coordination with the Trump presidential campaign, repeated and willful self-dealing, and much more."
The lawsuit names the president, his sons Donald Trump Jr and Eric Trump, and his daughter Ivanka Trump, who were on the board of the foundation.
The suit seeks $2.8 million in restitution and to bar Trump, Don Jr, Eric and Ivanka from serving on the boards of other New York non-profits.
Trump has repeatedly refused to release his personal income tax returns and legal efforts are underway in Congress and New York to obtain them.
New York prosecutors are looking into the millions of dollars in funding for Trump's 2017 inauguration ceremony, including whether any money was received from foreign donors.
Democratic-led committees in the House have been investigating allegations of obstruction of justice, abuse of power, Trump's finances, election campaign funding and other areas.
Pelosi announced on Tuesday that the various probes being conducted by 6 committees would be grouped under the umbrella of a formal impeachment inquiry.
"The president must be held accountable," she said. "No one is above the law."
Special Counsel Robert Mueller concluded his probe of Russian meddling in the 2016 election without recommending any charges be filed against a sitting president.
Trump is facing several lawsuits alleging he has used his office to enrich himself and violated the "foreign emoluments clause" of the Constitution.
The emoluments clause prohibits a president or other office-holder from profiting from their dealings with foreign governments.
Trump's proposal, for example, that next year's Group of Seven (G7) summit be held at his luxury resort in Florida prompted an outcry that it would violate the clause.
The attorneys general of Maryland and Washington filed a suit over Trump's continued ownership of a hotel in Washington frequented by lobbyists, company executives and foreign governments.
That suit was thrown out by an appeals court last month but a separate emoluments suit brought by Democrats in Congress is continuing. – Rappler.com