The first presidential debate between Donald Trump and Democratic rival Joe Biden was a low point for modern political and presidential electoral history in the United States, a Washington correspondent says.
Washington correspondent Simon Marks said the debate was absolutely shameful and showed how far the US has "drifted from its constitutional and democratic moorings".
"This was far and away the low point for modern political presidential and electoral history in the United States ... in large part, I think one has to say, because of the abject refusal of President Trump to allow Joe Biden to get a sentence out, or the abject refusal of President Trump to observe the rules of the debate."
But nor did Joe Biden shine in the debate, Marks said.
Although he said Biden did put to rest Trump's allegation that he lacks cognitive ability.
"But he just struggled to get his points across because Donald Trump wouldn't leave him alone."
Marks said for much of the debate the two men were talking over each other until the debate's moderator, Chris Wallace of Fox News, intervened.
"At times all three men were raising their voice in a bid to try and control the debate's narrative - it's almost hard to point to highlights."
The New York Times has reported that Donald Trump has paid very little income tax in recent times as heavy losses from his enterprises offset hundreds of millions of dollars in income.
Wallace quizzed Trump over his taxes.
"Is it true that you paid $750 in federal income taxes each of those two years?," Wallace asked Trump.
"I've paid millions of dollars in taxes, millions of dollars in income tax and let me just tell you there was a story in one of the papers that I paid $38 million one year, I paid $27m one year," Trump said.
Marks described Trump's tax statement as a "bald faced lie" saying that it's evident from the New York Times that he only paid $750 in 2016 and 2017.
Marks said there were moments when he thought Joe Biden might unclip his microphone and walk away from the stage and at another time he thought the moderator might walk away.
"I wonder if there really are going to be two more presidential debates," Marks said.
The debate got very ugly after Trump attacked Biden's son, Marks said, and it was obvious that Biden was reining in his anger.