The House of Representatives carried out months of investigation before impeaching Trump, and it, no doubt, has thousands of pages of documentary evidence and the testimony of dozens of witnesses to rely on. This is the material that the House managers drew upon during their 24 hours of so-called opening arguments, taking that opportunity to sneak in as much of the evidence as they could. Trump’s counsel also had 24 hours, to respond to the managers’ claims. Senators, acting as both judges and jury, had the opportunity to question both sides. What more do we need?

A lot, as it turns out. The thing that was missing is confrontation, which inevitably means cross-examination.

The main point of cross-examination is to challenge the veracity of the other side’s evidence. A competent witness must be able to observe, remember, and recount what happened, and there’s always the question of conscious or unconscious bias. The party calling the witness has every reason to put her in the best light possible; it’s the opposing party who wants to discredit her. And that’s best done through cross-examination, which John Henry Wigmore, the dean of the law of evidence, once famously described as “beyond any doubt the greatest legal engine ever invented for the discovery of truth.” In nearly every impeachment proceeding that has made it to the Senate before now, including the basely partisan impeachment of Andrew Johnson, the managers and the defense have called, examined, and cross-examined witnesses.

Things changed with Bill Clinton’s impeachment. During his trial the Senate heard from only three people, and then only via select segments of videotaped depositions. But 12 years later, in the impeachment of Judge Thomas G. Porteous Jr., it was back to a typical trial with witnesses, and before dismissing the case against Judge Samuel B. Kent in 2009, the Senate gave the country no reason to think that it wouldn’t hear witnesses in that trial. The rule now seems to be that when Congress impeaches a judge, it holds a regular trial, but when it impeaches a president it adopts a Frankenstein process designed for grandstanding that in the end amounts to nothing but sound and fury.

In the Trump impeachment debacle, even the opening and closing arguments, and the senators’ questioning process, were terribly flawed. The opening arguments weren’t designed to let the managers and the president’s counsel test the truth of the other side’s assertions. There was a lack of spontaneity; the managers spoke without interruption by the defense for more than 20 hours, raising a host of legal issues and making innumerable factual allegations, all of it likely blurring in the minds of the senators. Any high-school debater knows that the better approach is a series of brief presentations that involve immediate point-by-point rebuttals. Simply put, there was no dialogue.