Tom Daschle, a Democrat, represented South Dakota in the U.S. Senate from 1987 to 2005. Trent Lott, a Republican, represented Mississippi in the Senate from 1989 to 2007.

Can today’s Senate, consisting of senators holding strongly opposed views and representing a deeply divided nation, put aside those differences and conduct a fair, nonpartisan presidential impeachment trial, if it comes to that? It is a challenge with a high degree of difficulty, but we believe it can and must be done. And we hope senators will look to the Senate’s last presidential impeachment trial as a model.

In December 1998, the House of Representatives approved articles of impeachment against President Bill Clinton, leaving to us, as the then-majority and minority leaders, the task of negotiating procedures for a trial in the Senate. This was not easy; while we were committed to “do impartial justice,” as our impeachment trial oath required, we had very different perspectives on key questions — as did our caucuses — and, indeed, those differences remained throughout the trial and the final vote. But from the outset of our negotiations, we both understood how vitally important it was to rise above those differences in order to conduct a trial that would inspire the confidence of the public and withstand the unsparing scrutiny of history.

The Senate has a set of impeachment rules that date to 1798, and they were last updated in 1986. They provide a helpful framework for a trial, but are silent on many important issues, such as: How long should the trial be? How much time should each side be allowed to make its case? Should witnesses be called? If so, how many, and which ones? Should witnesses testify on the Senate floor or be deposed elsewhere? When should a motion to dismiss the articles of impeachment be in order, and for how long should the Senate debate it?

In negotiating answers to these questions and putting those agreements in writing, we felt fairness required us to ensure that neither side be given any procedural advantage — in fact or appearance — that might taint the proceedings. We also decided to err on the side of allocating more rather than less time for testimony and debate, so both sides would be comfortable that their arguments had been fully heard. Given breaks for depositions to be taken and the need to accommodate the chief justice, who would preside over the trial in addition to his duties at the Supreme Court, we understood that the Senate would have to devote a substantial amount of time to the trial.

Before trial procedures were adopted, the entire Senate convened for a closed session in the Old Senate Chamber to mark the constitutional moment and agree in principle that the trial should be conducted fairly and in fidelity to constitutional precedent. Out of the glare of television lights, the Senate truly acted as the great deliberative body it was intended to be. Senators addressed their responsibility soberly and in a spirit of collegiality. This meeting set the tone for the balance of the trial process.

The Senate then voted on two resolutions implementing our negotiated terms for the trial. The first and more important of the two, governing time allocations, was adopted by a vote of 100-0. The subject of the second, governing certain details regarding depositions, was more contentious, but the handling of those depositions was later worked out in a way both sides could live with.

On Jan. 7, 1999, the trial began. The ensuing five weeks were filled with passionate arguments and extensive debate about whether the Constitution demanded conviction of the president. Lawyers for both sides were given ample time to be heard, and senators were given ample time to ask questions, review evidence and deliberate. The Senate, and much of the nation, watched with rapt attention. On Feb. 12, the Senate voted on two articles of impeachment, neither of which attained the necessary two-thirds supermajority for conviction. Not everyone was happy with that outcome. But we heard almost no complaints about the trial itself.

We remain proud that the Senate rose to meet its constitutional duty, and did so in a manner that most observers concluded was fair and impartial. If called upon to hold another presidential impeachment trial, we hope senators of both parties will again put aside partisan considerations and approach the task with the same spirit of fairness that served the institution of the Senate and the country so well two decades ago.

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