As president of the United States, Donald Trump enjoyed unique protection from legal action, be it criminal or civil.
Now, after losing the 2020 presidential election, Mr Trump will soon become a private citizen again.
That means he will lose his presidential privileges, putting him in the crosshairs of litigators and prosecutors.
"Once he is out of office, the atmosphere will change," Daniel R Alonso, a former US federal and New York state prosecutor, told the BBC. "He will no longer have the reality or the threat of presidential power to thwart investigations."
A wide-ranging criminal investigation in New York is the most serious legal concern for Mr Trump and his real-estate company, the Trump Organization.
On top of that, there is an array of lawsuits ranging from allegations of fraud by a family member to sexual harassment by an advice columnist.
A legal storm is brewing. Here, we consider how the six biggest legal battles may develop.
1) The hush-money allegations
What we know: Playboy model Karen McDougal, adult film actress Stormy Daniels and claims of a conspiracy of silence.
This was the gist of the so-called hush-money scandal. Both women said they had had sexual relationships with Mr Trump and had received payments to keep them quiet, ahead of the 2016 presidential election.
When they spoke out in 2018, they threw political dynamite under Mr Trump's presidency, lighting the fuse of two criminal investigations.
The first focused on violations of federal, or national, laws and the role of Michael Cohen, Mr Trump's former personal lawyer and "fixer".
Under investigation, Cohen admitted to arranging payments to the two women. The payments were prosecuted as campaign-finance violations and Cohen was sentenced to three years in jail in 2018.
Cohen alleged that Mr Trump had "directed" him to make the payments, yet no charges were brought against the president. Why?
Firstly, to charge Mr Trump, prosecutors would have needed to prove that he had indeed directed Cohen to make those payments. Secondly, even if prosecutors did have sufficient evidence, it is against US government policy to indict a sitting president on federal criminal charges, legal experts say.
Case closed, right? Well, not exactly. This is where it gets technical.
Put simply, a second criminal investigation into the payments is still under way in New York.
We know that Manhattan District Attorney Cyrus Vance is examining whether the Trump Organization falsified business records related to the payoffs.
What we don't know is whether Mr Vance has any evidence to file criminal charges. That matters.
What might happen next: Falsifying business records is a misdemeanour under New York law. A misdemeanour is a minor crime that can be punishable by a jail term of up to a year.
Now, here's the tricky part for Mr Vance.
Trump accused of directing hush money
Will Trump remain bulletproof after Cohen?
There is a two-year time limit for filing criminal charges for a misdemeanour in New York.
"So, because those payments happened over two years ago, it looks like [prosecutors] are out of luck," Mr Alonso said.
That said, there are other possibilities.
In New York, falsifying business records can be charged as a felony if it is done to conceal other crimes, such as tax fraud.
Felonies are more serious crimes that can be prosecuted over a longer period and are punishable by tougher jail sentences.
Still, the route to prosecution is uncertain. It is not clear if Mr Trump can be prosecuted under New York law for campaign-finance violations - the federal crime Cohen was jailed for.
This is where the other strands of Mr Vance's investigation come in.
2) The tax and bank fraud investigation
What we know: It's a "political hit job", a Trump Organization lawyer said of Mr Vance's inquiry in August 2019.
The lawyer's statement was seething.
Mr Vance had just issued a request for documents, known as a subpoena. He demanded to see years of financial records, including the Holy Grail - Mr Trump's tax returns, eight years of them.
Since then, Mr Trump has tried to block the subpoena, arguing in courts that it amounts to political harassment. In October, a federal appeals court disagreed, putting his tax returns within touching distance of prosecutors.
Indeed, Mr Vance has stressed the significance of Mr Trump's tax returns in court papers.
When requesting the returns in August, Mr Vance referred to "public reports of possibly extensive and protracted criminal conduct at the Trump Organization", including allegations of possible insurance and bank fraud. Another court filing in September mentioned tax fraud as a hypothetical crime that could be established, should evidence be found to support it.
In New York, some types of tax fraud can be charged as felonies, which can carry lengthy prison sentences. At the moment, though, the "public reports" of possible crimes cited by Mr Vance's office are merely grounds for investigation, nothing else.
What might happen next: Mr Trump is expected to appeal against the demand to hand over his tax returns in the Supreme Court. There, the matter may be settled.
3) The real-estate fraud investigation
What we know: New York Attorney General Letitia James has been another thorn in Mr Trump's side.
Since March 2019, Ms James has been leading a civil investigation into whether the Trump Organization committed real-estate fraud.
Again, the roots of this investigation lead back to Cohen who, in February 2019, told Congress that Mr Trump had inflated the value of his property assets to secure loans and understated them to reduce his taxes.
Cohen's testimony gave Ms James grounds to seek information about Mr Trump's property empire. Like Mr Vance, Ms James has had to fight for that information in the courts.
Eric Trump, the executive vice-president of the Trump Organization and the president's son, has accused her of waging a "political vendetta". Despite this, he complied with a request to sit for testimony with her office in October.
What might happen next: Ms James needs more testimony and information to take the investigation forward.
In office, Mr Trump argued that he was too busy to deal with lawsuits. Now, he cannot use that excuse.
Ms James can treat Mr Trump with less deference, pressing him to sit for questioning under oath, just like his son.
4) The emoluments cases
What we know: Emolument is an archaic word that is seldom used today, except in legal contexts. The definition is contested, but it is generally understood to mean gain, profit or advantage from employment or holding public office.
So what does this have to do with Mr Trump?
He has been accused of breaking rules against "emoluments" during his presidency. These rules, known as the emoluments clauses, were written into the country's bedrock legal text, the US Constitution.