Midway through Sunday's debate, Trump aggressively condemned Clinton's use of a private email server while serving as secretary of state. When Trump interjected during Clinton's response, Cooper told Trump to let the Democratic presidential nominee speak.
"Please allow her to respond, she didn't talk while you talked," Cooper said.
"That's true, I didn't," Clinton said, smiling.
"Because you had nothing to say," Trump shot back.
See photos from the tense debate:
"I didn't in the first debate, and I'm trying not to in this debate," Clinton said.
"And get off this question," Trump said.
Clinton then knocked the real-estate mogul over the fallout from the release of a video on Friday of Trump boasting about grabbing and kissing women without their consent.
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"I know you're into big diversion tonight, anything to avoid talking about your campaign and the way it's exploding and the way Republicans are leaving you, but let's at least focus on the issues that some people care about," Clinton said.
When Cooper attempted to turn to a question from an audience member, the real-estate mogul cut in.
"I'd like to know, Anderson, why aren't you bringing up the emails?" Trump said.
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"We brought up the emails," Cooper responded.
"No it hasn't, it hasn't, and it hasn't been finished," Trump said.
As he walked back toward his stool, the Republican presidential nominee got in one final barb.
"It's nice to — one-on-three," Trump said, referencing the moderators.