Former U.S. President Donald Trump has made history by becoming the first former president to face criminal charges, as he has been indicted for his involvement in paying hush money to porn star Stormy Daniels before the 2016 election. The indictment, brought by Manhattan District Attorney Alvin Bragg, a Democrat, sees Trump expected to surrender and attend his arraignment on Tuesday. Trump’s lawyers, Susan Necheles and Joe Tacopina, maintain his innocence.

The case against Trump may prove difficult for prosecutors due to their reliance on the testimony of Michael Cohen, a former Trump attorney who has faced his own legal issues. Cohen claims that Trump instructed him to pay Daniels $130,000 to keep quiet about an alleged affair. Trump denies both the affair and any involvement in the payment.

Despite the charges, a conviction would not affect Trump’s eligibility for presidential candidacy. The U.S. Constitution does not require presidential candidates to have a clean record, and states are not allowed to impose their own restrictions. Trump has stated he will continue in the presidential race regardless of the criminal charges.

Cohen’s credibility as a witness may be an issue in the case, given his history as Trump’s fixer and his own legal convictions. However, his account of Trump’s role in the hush-money payment has circumstantial support, including phone records and testimonies from Trump’s allies in the tabloid world. The case is far from a sure bet, as previous attempts to bring charges against Trump in a stand-alone case related to the hush money have not been successful. Trump has used the threat of prosecution to rally his base, raise campaign funds, and argue that he is being unfairly charged for political reasons.