26 U.S.C. § 6701: Penalties for aiding and abetting understatement of tax liability

who aids or assists in, procures, or advises with respect to, the preparation or presentation of any portion of a return, affidavit, claim, or other document, who knows (or has reason to believe) that such portion will be used in connection with any material matter arising under the internal revenue laws, and who knows that such portion (if so used) would result in an understatement of the liability for tax of another person, Except as provided in paragraph (2), the amount of the penalty imposed by subsection (a) shall be $1,000. If the return, affidavit, claim, or other document relates to the tax liability of a corporation, the amount of the penalty imposed by subsection (a) shall be $10,000. If any person is subject to a penalty under subsection (a) with respect to any document relating to any taxpayer for any taxable period (or where there is no taxable period, any taxable event), such person shall not be subject to a penalty under subsection (a) with respect to any other document relating to such taxpayer for such taxable period (or event). ordering (or otherwise causing) a subordinate to do an act, and knowing of, and not attempting to prevent, participation by a subordinate in an act. For purposes of paragraph (1), the term “subordinate” means any other person (whether or not a director, officer, employee, or agent of the taxpayer involved) over whose activities the person has direction, supervision, or control. Subsection (a) shall apply whether or not the understatement is with the knowledge or consent of the persons authorized or required to present the return, affidavit, claim, or other document. For purposes of subsection (a)(1), a person furnishing typing, reproducing, or other mechanical assistance with respect to a document shall not be treated as having aided or assisted in the preparation of such document by reason of such assistance. Except as provided by paragraphs (2) and (3), the penalty imposed by this section shall be in addition to any other penalty provided by law. No penalty shall be assessed under subsection (a) or (b) of section 6694 on any person with respect to any document for which a penalty is assessed on such person under subsection (a). No penalty shall be assessed under section 6700 on any person with respect to any document for which a penalty is assessed on such person under subsection (a).