Thursday was constitutional analysis day in the Senate’s impeachment trial of President Trump, which means the House managers’ case got more complicated, more abstract — and that much harder to hold the audience’s attention.

This is not a dig at the prosecution. As on Wednesday, when they spent eight hours constructing a detailed blueprint of Mr. Trump’s misbehavior, the managers threw themselves — with gusto — into explaining the constitutional ins and outs of impeachment. And just as before, they came equipped with slides, photos and video clips. They even brought instructional materials for the senators.

Their preparedness is impressive. Even Representative Matt Gaetz, the devoted Trump cheerleader from Florida, observed earlier this week that, thus far, the Democrats’ presentation looked as though it was “cable news” while the president’s defense team’s looked like “an eighth-grade book report.”

That said, while Wednesday’s narrative of presidential scheming and obstruction was a nonstop pile-on of damning testimony and other hard evidence, Thursday’s argument began with a lengthy seminar by one of the House managers, Representative Jerry Nadler, on the framers’ intent regarding impeachment.