Donald Trump's second impeachment trial was declared constitutional in a 56-44 vote on Tuesday, and so now the trial proceeds. The part that comes next, beginning at 12pm ET Wednesday: Each side gets up to 16 hours for opening arguments, with House impeachment managers up first. They plan to show Capitol security footage that hasn't previously been made public, with senior aides on the House impeachment team telling CNN it will make the case that "extreme violence" occurred on Jan. 6. They didn't provide details on its content or source. Aides tell the AP that over two days the managers intend to convey a "succinct" story that has an arc, beginning with Trump's false election fraud claims and ending with the riot. (More Trump impeachment stories.)