Just doing a little research and can find legislation that covers truthfulness in civil cases but not yet in criminal. I would assume there would be something of the same type. In civil cases it is governed by Rule 11(a) of the Federal Rules of Civil Procedure states as follows (BBM):
Rule 11. Signing and verification of pleadings.
(a) Signing by Attorney. - Every pleading, motion, and other paper of a party represented by an attorney shall be signed by at least one attorney of record in his individual name, whose address shall be stated. A party who is not represented by an attorney shall sign his pleading, motion, or other paper and state his address. Except when otherwise specifically provided by rule or statute, pleadings need not be verified or accompanied by affidavit. The signature of an attorney or party constitutes a certificate by him that he has read the pleading, motion, or other paper; that to the best of his knowledge, information, and belief formed after reasonable inquiry it is well grounded in fact and is warranted by existing law or a good faith argument for the extension, modification, or reversal of existing law, and that it is not interposed for any improper purpose, such as to harass or to cause unnecessary delay or needless increase in the cost of litigation. If a pleading, motion, or other paper is not signed, it shall be stricken unless it is signed promptly after the omission is called to the attention of the pleader or movant. If a pleading, motion, or other paper is signed in violation of this rule, the court, upon motion or upon its own initiative, shall impose upon the person who signed it, a represented party, or both, an appropriate sanction, which may include an order to pay to the other party or parties the amount of the reasonable expenses incurred because of the filing of the pleading, motion, or other paper, including a reasonable attorney's fee.
Experienced lawyers would know what they can and cannot do in a motion. Obviously this particular rule is relevant to civil cases. Hopefully I, or someone with a bit more know how that me, can find something similar in respect of criminal cases.
All IMO