While the debate started off somewhat civilly with each man nodding towards the other and saying “How’s it going?” the debate quickly became contentious with lots of over-talking and side comments, eventually leading to Biden’s comment.

Biden’s comments came in a segment in which both men discussed taxes and their respective tax plans. Fox moderator Chris Wallace asked Trump about a recent New York Times investigative report alleging that Trump only paid $750 in taxes during both 2016 and 2017 while also writing off extravagant personal expenses as deductions.

The report also claimed that for 10 of the previous 15 years, Trump paid no income taxes at all, “largely because he reported losing much more money than he made.”

Before the debate, Trump called the story “totally fake.” During the debate, Trump claimed he had paid millions of dollars worth of taxes, to which Biden repeatedly commented, “Then show us your tax returns.”

Although Trump said he would “as soon as they are done,” he then didn’t specify when that would be when asked by Biden.

Biden then commented that Trump had taken advantage of the tax code to pay less in federal income taxes than a school teacher.

When Biden then pledged to eliminate the Trump era tax codes to “invest in the people who in fact need to help people out there,” Trump asked, “But why didn’t you do it over the last 25 years?” a reference to Biden’s long political career.

As he and Biden began talking over each other, Biden then made his comment, “You’re the worst president America has ever had.”

Biden echoed this belief later in the debate when he said, “Under the Trump administration, America has become weaker, sicker, poorer and more divided.”

Trump retorted, “Let me just say, Joe, I’ve done more in 47 months, I’ve done more than you’ve done in 47 years, Joe.”

When asked later on why American voters should re-elect him, Trump said, “There has never been an administration or a president who has done more than I have done in three and a half years.”