What are the rules for the first debate between Donald Trump and Joe Biden?

President Donald Trump is not a man accustomed to following anyone else’s rules.

And yet, Tuesday’s debate will try to contain Trump and former Vice President Joe Biden within a set of loosely defined ground rules that Chris Wallace, the Fox News host moderating the event, will aim to enforce.

The Commission on Presidential Debates has divided the 90-minute event, the first of three presidential debates in the coming weeks, into six 15-minute segments. Wallace has selected six broad topics: Trump’s and Biden’s political records, the Supreme Court, the coronavirus, the economy, race and violence in cities, and the integrity of the election.

Wallace will begin each segment with a question. The person asked the question will have two minutes to respond, and the candidates will then have time to respond to each other.

Wallace won’t fact-check the candidates during the debates, the debate commission’s co-chairman said Sunday on CNN. The question of moderators fact-checking the candidates has long been a sensitive debate subject, never more so than when Candy Crowley of CNN told Mitt Romney he was wrong in saying President Barack Obama had not immediately called the 2012 Benghazi attack an “act of terror.”

The biggest task for Wallace in enforcing the rules may be keeping the candidates on the topic at hand. Biden has made it clear he wants the focus of the campaign to be healthcare — which is not one of the six designated topics — while Trump is not known for answering specific questions that are posed to him, or for keeping to his personal space.

Four years ago, during a town-hall-style debate, Trump wandered around Hillary Clinton as she spoke, looming behind her and remaining in the camera shot even while it wasn’t his turn to speak.

Biden was an inveterate rule follower during the Democratic primary debates, to the point of cutting himself off mid-answer at a gathering in June 2019 with a statement that at the time felt like a gaffe for the 76-year-old: “My time is up.”