Brendan McDermid / Reuters

Senate Majority Leader Mitch McConnell is in the midst of discussions about the shape and scope of the forthcoming impeachment trial of President Donald Trump. His most recent public offer is to adopt the same rules for Trump’s impeachment as those used in President Bill Clinton’s. He says he has the votes to impose that process on the Senate, even if Democratic senators object. On the surface, that seems a perfectly plausible proposal—after all, what is sauce for the goose might be thought sauce for the gander. Rules that were appropriate for Clinton should be appropriate for Trump.

But while it has a patina of reasonableness, the offer is little more than posturing.

Let’s begin with the Clinton impeachment (an investigation in which I participated as senior counsel to Independent Counsel Ken Starr). Clinton’s impeachment derived directly from a criminal investigation into perjury and obstruction of justice charges. That investigation took nine months. It was conducted by Starr along with more than two dozen lawyers and investigators, who interviewed nearly 100 witnesses and used the compulsory power of the grand jury to secure hundreds of hours of live testimony and tens of thousands of relevant documents. President Clinton resisted the investigation through the assertion of various privileges, but virtually all of those assertions were rejected by the courts, and the witnesses were required to testify truthfully. In the end, even Clinton himself testified and submitted a blood sample for DNA testing.

So when the referral for impeachment was sent to the House of Representatives, it was accompanied by a detailed record of what had transpired, comprising thousands and thousands of pages of documents and grand-jury transcripts. The facts were so little in doubt that the majority-Republican Judiciary Committee called only a single witness—Independent Counsel Starr—to summarize the case.

When the matter moved to the Senate for trial, the House managers sought authority to call witnesses, but not because they needed more factual development. Rather, their argument was that the Senate, as a trier of fact, had to look the witnesses in the eye and assess their credibility. The senators did not need to ask, “What will Monica Lewinsky say?” because the record of what she would say was clear. Instead, the House argued, the Senate needed to ask, “Is Lewinsky telling the truth?” and to do that, it needed to hear from her directly.

But the Senate managed to dodge the question of credibility. After hearing opening statements from the House managers (who are essentially prosecutors) and from Clinton’s defenders, it rejected the House request to call 10 witnesses. After some negotiations, the Senate authorized the deposition of three witnesses, who were interviewed off the Senate floor with only a few senators present. Although the Senate allowed the House to call these witnesses, it appears to have decided the matter without assessing the witnesses’ credibility directly. The dominant view in the Senate seems to have been that even if everything Starr and the House alleged was true and even if the witnesses were fully credible, the offenses alleged (lying under oath about a private sexual matter) did not rise to the level of “high crimes and misdemeanors” worthy of impeachment. Whether witnesses were being truthful was almost beside the point.

If, last year, the House had chosen to act on impeachment in response to the report from Special Counsel Robert Mueller, one might reasonably think that the two impeachments were procedurally related. Both would have been grounded on an extensive pre-impeachment criminal investigation. But the House grounded its impeachment not in Mueller’s report but in the Ukrainian bribery scheme, and reached its decision to impeach Trump through a radically different process than was used for Clinton.

There was no pre-impeachment criminal investigation of Trump’s efforts to compel Ukraine to pursue the alleged corruption of his political opponent. There were no lawyers and FBI investigators interviewing witnesses. There was no grand jury—merely the cumbersome House-committee process. That process didn’t last nine months; it lasted less than three. Rather than produce tens of thousands of documents, the White House and the executive branch withheld almost all those subpoenaed by the House. Likewise, rather than eventually allowing executive-branch witnesses to testify, the White House stonewalled the House inquiry: President Trump successfully frustrated the House’s efforts to hear from witnesses like former White House Counsel Don McGahn and former National Security Adviser John Bolton. And of course, President Trump never told his side of the story under oath.

So, unlike with Clinton, the Trump impeachment investigation is incomplete. Far from being given an exhaustive record on which to make a determination, the Senate has received only part of the story from the House. The Senate is not in the position of wondering whether, for example, John Bolton was truthful in what he has said already. Rather, if he is called to testify, the Senate will hear what he has to say for the first time. The process now isn’t about credibility; it’s about establishing facts.

Senator McConnell’s proffered analogy to the Clinton impeachment is ill-considered, if not disingenuous. While the Senate might, with some justification, have thought that the evidence was complete and that no witnesses were necessary to decide the Clinton matter, it cannot reasonably make the same claim now. Though the analogy of a House impeachment to a grand-jury indictment is rather strained, it does carry a bit of truth: The House has found sufficient evidence to start an impeachment trial, and it is up to the Senate now to conduct a more in-depth inquiry—a trial. Trials are for hearing evidence. That task lies before the Senate.

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