The riot at the Capitol on January 6 was the direct result of a campaign by former President Donald J. Trump to undermine American democracy and overthrow the election at any cost, the House impeachment managers will argue in his Senate trial. They warn that acquitting him and failing to disqualify him from future office could do grave damage to the nation.

In a meticulously detailed 80-page pre-trial brief filed with the Senate on Tuesday, the nine House Democrats preparing to prosecute the case next week argued that Trump was “singularly responsible” for a violent attack on the democratic process, and would do anything to “reassert his grip on power” if he were allowed to seek election again.

“That outcome is not only supported by the facts and the law; it is also the right thing to do,” wrote the managers. “President Trump has demonstrated beyond doubt that he will resort to any method to maintain or reassert his grip on power. A President who violently attacks the democratic process has no right to participate in it.”

Addressing Republicans’ arguments head on, they also asserted that history and even conservative constitutional theory supported the Senate’s right to try a former President.