In a 1999 memo from then-Sen. Joe Biden (D-DE), Biden strongly warned against allowing new witnesses or evidence to be brought into the Senate impeachment trial of President Bill Clinton.

The memo, obtained by Politico, showed Biden citing numerous historical precedents from prior impeachment cases and even argued that “the Senate need not hold a ‘full blown’ trial.”

“The Senate may dismiss articles of impeachment without holding a full trial or taking new evidence. Put another way, the Constitution does not impose on the Senate the duty to hold a trial,” Biden wrote, later adding, “In a number of previous impeachment trials, the Senate has reached the judgment that its constitutional role as a sole trier of impeachments does not require it to take new evidence or hear live witness testimony.”

Biden even warned against allowing the trial to be drawn out, writing, “In light of the extensive record already compiled, it may be that the benefit of receiving additional evidence or live testimony is not great enough to outweigh the public costs (in terms of national prestige, faith in public institutions, etc.) of such a proceeding,” Biden said. “While a judge may not take such considerations into account, the Senate is uniquely competent to make such a balance.”

The article quickly went viral and Republican Senators, who were sitting in the Senate trial, immediately asked a question about the Biden’s 1999 memo, calling it the “Biden rule.”

Here it is: Why should the "Biden rule" not apply here? End the impeachment sham now. https://t.co/kzLSnWOJdC pic.twitter.com/Bo7ZVnjNFP — Christian Martinez (@C_RMartinez) January 31, 2020

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