Rule 19-303.3 Candor Toward the Tribunal [MARPC 3.3]
(a) An attorney shall not knowingly:
(1) make a false statement of fact or law to a tribunal or fail to correct a false statement of material fact or law previously made to the tribunal by the attorney;
(2) fail to disclose a material fact to a tribunal when disclosure is necessary to avoid assisting a criminal or fraudulent act by the client;
(3) fail to disclose to the tribunal legal authority in the controlling jurisdiction known to the attorney to be directly adverse to the position of the client and not disclosed by an opposing attorney; or
(4) offer 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.
(b) The duties stated in section (a) of this Rule continue to the conclusion of the proceeding, and apply even if compliance requires disclosure of information otherwise protected by Rule 19-301.6 (1.6).
(c) An attorney may refuse to offer evidence that the attorney reasonably believes is false.
(d) In an ex parte proceeding, an attorney shall inform the tribunal of all material facts known to the attorney which will enable the tribunal to make an informed decision, whether or not the facts are adverse.
(e) Notwithstanding sections (a) through (d) of this Rule, an attorney for an accused in a criminal case need not disclose that the accused intends to testify falsely or has testified falsely if the attorney reasonably believes that the disclosure would jeopardize any constitutional right of the accused.