It's unclear what federal prosecutors in NY will decide to do if they conclude that there is evidence that Trump himself committed a crime. It is called "advice of counsel", and a lawyer has great liability if a mistake is made.
Trump has denied the alleged affairs with the women.
An emotional Cohen told the court he accepted responsibility for his personal crimes and "those involving the President of the United States of America".
In addition to life behind bars, the former Trump confidant is also subject to forfeiture of $500,000, restitution of $1.4 million and fines totaling $100,000. The two terms will run simultaneously. He was ordered to surrender on March 6. In addition to the jail term, he was also ordered to forfeit almost $2m (£1.6m).
Judge Pauley described the crimes as a "smorgasbord of fraudulent conduct" marked by deception and "motivated by personal greed". His 23-year-old daughter, Samantha, and 19-year-old son, Jake, both wept silently in the courtroom, the son wiping his eyes with his jacket sleeve. Cohen's light sentence may have another value, though.
Cohen's father, Maurice Cohen, who showed little emotion during the hearing, later told reporters: "My heart is ripped".
Cohen was on Wednesday sentenced to three years in jail for crimes including tax evasion, bank fraud and lying to Congress.
The Cohen case has intensified the legal pressures on former reality television star Trump, whose almost two-year presidency has been clouded by multiple investigations and lawsuits, including a USA special counsel probe into alleged Russian meddling in the 2016 election, possible collusion between Moscow and Trump's campaign and possible obstruction of justice.
After Cohen's sentencing made headlines, Trump went on a tweetstorm attacking his former right-hand man.
Cohen's crimes included working with American Media Inc to buy the silence of a model who said she had an affair with Mr Trump.
Federal law requires that the contribution of "anything of value" to a campaign must be disclosed, and an individual donation can not exceed US$2,700.
The Adorable 2018 Royal Family Christmas Cards Are Here
After Prince Louis was born, Kensington Palace released a pic of the new big sister wearing (you guessed it) George's cardigan. The 2018 Christmas card of the Prince of Wales and Duchess of Cornwall on a Christmas tree in Clarence House, London .
He also said that Trump "doesn't tell the truth, and it is sad that I should take responsibility for his dirty deeds".
The Mueller investigation represents a threat to Trump's presidency. And if it was a prohibited contribution, Trump said, Cohen is the one who should be held responsible.
The objective of the payments had been to "help [Trump] and his campaign", he added. As for whether Trump knew it was illegal, he said, "Of course". Cohen said that Trump knew it was wrong, but did it anyway, "to help him and the campaign".
"So, (Trump's) still lying?"
This week, Trump said on Twitter that the payments were a "private transaction" and not at all related to the campaign.
What's more, Cohen has said he paid the hush money at Trump's direction, and even though the prevailing view at the Justice Department is that a sitting president can't be indicted, Manhattan prosecutors could still consider charging Trump after he leaves office.
Cohen fired back, "I did not do it to embarrass the president".
The admissions by Cohen and AMI conflict with Trump's own evolving explanations.
In the interview, though, Cohen denied that.
"Nobody except for me would be looked at like this, nobody", he said. Trump can claim that he had no idea it would violate FEC regulations to do so, and in fact there is still quite a bit of debate as to whether it actually did (see above).
Trump, who is also trying to fend off a huge probe of his election campaign's contacts with numerous Russian officials, describes the mounting legal assault as a "witch hunt".
Is Trump in real trouble? The project was never built.