Couple things regarding the debate. There's a scenario where the mics may be unmuted. Also, Trump won a coin toss and decided to go last in closing statements.
The Harris campaign also told CBS News that it was offered assurances that the microphones may be unmuted if there is significant crosstalk between the candidates. A candidate who constantly interrupts their opponent will be warned by the moderator and their comments may be relayed to the audience. And, if the microphones don't pick up the exchanges, a group of reporters who will be in the room would be able to report anything noteworthy.
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A coin toss was held virtually on Sept. 3, with the candidate who won the coin toss allowed to choose the order of the closing statement or podium placement. Trump won the coin toss and chose to select the order of statements, ABC News said. The former president chose offer the last closing statement.
Podium placement and candidate stage positions
After the coin toss, Harris was allowed to chose podium placement. She selected the podium position to the right on screen, ABC News said.