(Bloomberg Opinion) -- If you’re expecting President Donald Trump’s impeachment trial in the Senate to be a matter of high drama, it’s time to lower your expectations. The trial won’t look much like Law & Order, or for that matter any other criminal trial you’ve seen on TV or in real life: There will be no witnesses in the opening phase, and likely none at any point in the proceedings. Instead, it will look much more like a series of speeches by the House impeachment managers and Donald Trump’s lawyers.

How can it be that the impeachment trial will barely be a trial at all? The answer lies in the Senate’s own changing practices over the centuries. Given the Senate’s love for protocol, you might imagine that there would be some time-tested, universally respected procedure for how an impeachment trial should go. The truth is otherwise.

The Senate has been all over the map when it comes to impeachment trial procedures. The current procedures being proposed by Majority Leader Mitch McConnell bear some resemblance to the procedures followed in Bill Clinton’s impeachment trial in 1998-99. But those procedures were themselves radically different than the practices followed by the Senate in the early years of the republic.

The first impeachment undertaken by the House of Representatives was directed against Senator William Blount in 1797, for his involvement in a scheme intended to give Britain control over Florida and Louisiana to protect speculative land investments he’d made. The House of Representatives went to great pains to follow the procedures that had been used in Britain by the House of Commons in impeaching Warren Hastings, the former governor general of Bengal, before the House of Lords – a protracted affair that took place in fits and starts from 1788-95. A House member appeared in the Senate and announced that he was “commanded” by the house “to impeach William Blount … of high crimes and misdemeanors.”

Then things got messy. The very next day, the Senate voted to expel Blount from the Senate – and then spent months adopting detailed rules in anticipation of a trial. In his defense, Blount argued that he was no longer a senator, and that in any case the Constitution didn’t provide for the impeachment of senators at all, only members of the executive branch and the judiciary. After deliberations, the Senate voted 14-11 to dismiss the impeachment charges on the ground that the Senate did not have “jurisdiction” over the case. The Senate never did decide whether the problem was that Blount was no longer a senator or that senators weren’t subject to impeachment.

The next big development took place in 1831, when Judge Samuel Peck was impeached for issuing a contempt order against the author of an anonymous letter in a St. Louis newspaper criticizing one of Peck’s judicial opinions. At his trial, Peck’s lawyer sought to get opinion evidence from a witness -- evidence that would not have been admissible in a court of law. The House managers argued that the Senate trial should apply strict rules of evidence like those used in court.

The two sides fought it out, each relying on arguments that had been used in the Hastings trial some thirty years earlier. In that trial, Edmund Burke, the lead impeachment manager (famous today as the father of gradualist conservatism), had maintained that strict rules should not be followed because an impeachment differed from a criminal trial. His opponents, Hastings’ defenders, had argued for strict rules of evidence that would exclude lots of the material that the House of Commons had relied on in voting to impeach Hastings. They won — and Hastings was eventually vindicated after the evidence was excluded.

In the end, the Senate voted to follow strict rules of evidence in its own impeachment trials. That norm continued to hold through the impeachment of Andrew Johnson and into the 20th century. The most important compendious guide to impeachments, Asher Hinds’ Precedents of the House of Representatives, published in 1907, still treated this decision as binding. The relevant chapter on “rules of evidence in an impeachment trial,” chapter 69 of volume 3, has a section headed “strict rules of the courts followed.”

But the Peck precedent eventually gave way. In 1974, law professor Charles Black argued in his influential handbook on impeachment that “Both the House and the Senate ought to hear and consider all evidence which seems relevant, without regard to technical rules.” The Senate relaxed the rules of evidence considerably in the impeachment trials of judges Harry Claiborne (1986) and Alcee Hastings (1989).

By the time Bill Clinton was tried, the new rules said only that the Chief “may rule on all questions of evidence including, but not limited to, questions of relevancy, materiality, and redundancy of evidence and incidental questions,” pursuant to being overturned by a majority of the senators. And much of the most important evidence against Clinton including Linda Tripp’s account of her conversations with Monica Lewinsky, would have been inadmissible hearsay that could not have been accepted as evidence in a court of law.

The upshot is that a majority of the Senate can make the impeachment trial into almost anything it wants. The Senate can treat the impeachment trial like a regular criminal trial, with witnesses and evidence, or it can turn the trial into a series of speeches. That’s what the sole power to try impeachment means -- for better or for worse.

To contact the author of this story: Noah Feldman at nfeldman7@bloomberg.net

To contact the editor responsible for this story: Sarah Green Carmichael at sgreencarmic@bloomberg.net

This column does not necessarily reflect the opinion of Bloomberg LP and its owners.

Noah Feldman is a Bloomberg Opinion columnist. He is a professor of law at Harvard University and was a clerk to U.S. Supreme Court Justice David Souter. His books include “The Three Lives of James Madison: Genius, Partisan, President.”

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