Although they aren’t exactly the same, Rules 3.3 of the Attorneys’ Rules of Professional Conduct in both Maryland and the District of Columbia prohibit a lawyer from “offer[ing} evidence that the attorney knows to be false. If an attorney has offered material evidence and comes to know of its falsity, the attorney shall take reasonable remedial measures.” MD Rule 19-303.3(a)(4). This Rule governs the conduct of an attorney who is representing a client in the proceedings of a tribunal which another Maryland Rule defines as “a court, an arbitrator in a binding arbitration proceeding or a legislative body, administrative agency or other body acting in an adjudicative capacity.”
IANAL, but it seems to me that offering altered evidence, for example, a tweet with an added blue check or one with an altered timestamp, would be a clear violation of Rule 3.3 and that failing to take remedial action compounds the violation. Surely, the Senate sitting as a court of impeachment is a body acting in an adjudicative capacity.
Jamin Ben Raskin is a member of the bars of both Maryland and DC.