The three-page memo, obtained by Politico and confirmed as authentic by The New York Times, included arguments from the chief counsel, Greg Jacob, that Mr. Pence could find himself in a legally precarious situation if he decided to block the certification of the Electoral College results either unilaterally or by calling for a 10-day delay in the proceedings…

Mr. Jacob wrote in the memo that Mr. Pence would most likely be overruled by the courts if he made such a move.

“In a best-case scenario in which the courts refused to get involved, the vice president would likely find himself in an isolated standoff against both houses of Congress, as well as most or all of the applicable state legislatures, with no neutral arbiter available to break the impasse,” Mr. Jacob wrote in the memo.