The trial of Donald Trump on charges of falsifying business records to conceal hush money paid to a porn star began in New York on Monday with opening statements from the prosecution and the defence.
In the first criminal trial of a former president in US history, prosecuting attorney Matthew Colangelo accused Trump, who was present in the courtroom, of attempting to influence the 2016 elections through the payment of $130,000 to adult film actress Stormy Daniels.
"It was election fraud, pure and simple," Colangelo said. "This case is about a criminal conspiracy and a coverup."
Daniels said the money was given to keep her quiet about an affair she had with Trump in 2006. He has admitted to paying her but denies any sexual encounter.
Trump is accused of 34 counts of falsifying business records as part of a scheme involving his former lawyer and fixer Michael Cohen to hide the pay-off made to Daniels.
The prosecution alleges that Trump, Cohen and David Pecker, the former editor of the National Enquirer tabloid, colluded to keep damaging stories out of the public eye ahead of the election.
Trump had orchestrated "a criminal scheme to corrupt the 2016 presidential election," Colangelo said by arranging for a "catch-and-kill" strategy in which the negative information was purchased, non-disclosure agreements signed and the stories promptly buried.
Three such pay-offs are alleged to have occurred, one involving a former doorman at Trump Tower in New York, another involving an alleged affair with Playboy model Karen McDougal and the alleged affair with Daniels.
In initial testimony on the first day, Pecker revealed details about how the National Enquirer went to work, describing its tactics openly "chequebook journalism." Pecker was acting on Trump's behalf, not as a publisher, but as a "co-conspirator," Colangelo said.
He is to testify further on Tuesday before being cross-examined by the defence.
Defence attorney Todd Blanche said that Trump had not committed any crimes. "President Trump is innocent," Blanche said, arguing there was nothing illegal about the non-disclosure agreement made with Daniels.
The former president was merely seeking to protect his family, Blanche said.
Trump, who is campaigning to win re-election in November as the Republican Party candidate, has pleaded not guilty to all the charges. He could face a prison sentence if found guilty, or a suspended sentence.
"There's nothing wrong with trying to influence an election ... It's called democracy," Blanche told the court. The money paid had been paid legally, he said.
Blanche called Cohen, who is one of the prosecution's key witnesses, a "criminal" who had previously lied under oath.
It was not clear at the start of the trial whether Trump or Daniels would take the witness stand.