A New York court opened an unprecedented criminal trial of a former U.S. president on Monday as Donald Trump faced the first of the four cases in which he has been indicted.

The trial, expected to last one to two months before a jury reaches a verdict, concerns an alleged coverup of hush money paid on his behalf to a porn star ahead of the 2016 presidential election.

A crowd including Donald Trump supporters and press people gathers on a street near a New York court where the former president was on trial on April 15, 2024. (Kyodo)

Trump is set to be nominated as the Republican presidential candidate for the November election at the party's national convention in July, and has insisted all the indictments are groundless.

"This is political persecution," Trump told reporters before entering the courtroom Monday.

During the session, the judge explained the trial procedures and the court began the multiple-day process of selecting a 12-member jury.

Trump, 77, was indicted in March last year for having his lawyer pay $130,000 to the porn star Stormy Daniels, with whom he was believed to have had an affair, as hush money before the 2016 election and falsifying the disbursement as legal fees in business records.

Prosecutors said the actions constituted a bid to conceal information that could have affected his chances in the election.

The former U.S. president has also been indicted over accusations of mishandling classified documents at his residence in Florida as well as in two cases related to attempting to overturn his 2020 election loss -- a federal case over actions that led to the fatal Capitol riot in January 2021, and another in Georgia for efforts to undermine that state's election processes.

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