26 U.S.C. §7201 Willful Failure to File:

Any person required under this title to pay any estimated tax or tax, or required by this title or by regulations made under authority thereof to make a return, keep any records, or supply any information, who willfully fails to pay such estimated tax or tax, make such return, keep such records, or supply such information, at the time or times required by law or regulations, shall, in addition to other penalties provided by law, be guilty of a misdemeanor and, upon conviction thereof, shall be fined not more than $25,000 ($100,000 in the case of a corporation), or imprisoned not more than 1 year, or both, together with the costs of prosecution. In the case of any person with respect to whom there is a failure to pay any estimated tax, this section shall not apply to such person with respect to such failure if there is no addition to tax under section 6654 or 6655 with respect to such failure. In the case of a willful violation of any provision of section 6050I, the first sentence of this section shall be applied by substituting ''felony'' for ''misdemeanor'' and ''5 years'' for ''1 year''

25 FR 11402, 11420, 12108-12113 (November 26, 1960) - republishing of FR on all of IRS part 1 with statutory authority 26 C.F.R. 1.6012-1 with the statutory Authority of 7805 and other CODE sections making it a substantive regulation with the force and effect of law.

Failure to File Defense Materials

THE ELEMENTS THE GOVERNMENT MUST PROVE ARE:

Defendant failed to file a return (47B C.J.S. 1258, note 89)

He must be a person required to make a return (47B C.J.S. 1258, note 93)

He must have done so "willfully" (47B C.J.S. 1258, note 90).

The word "willfully" in the Statute means "a voluntary, intentional violation of the known legal duty to file a return" (47B C.J.S. 1258, note 5), and the taxpayer's motives in failing to file such are immaterial and irrelevant (47B C.J.S. 1258, note 96). Some cases have construed the Statute as not requiring an intent to defraud the government or other similar bad purpose or evil motive (47B C.J.S. 1258, note 98).

"Willfulness" means "a voluntary intentional violation of a known legal duty" (47B C.J.S. 1256, note 45) which may be shown through consistent patterns of not reporting large amounts of income.
An act may be done knowingly and intentionally whether as the immediate act of the person charged, or his authorized act through an employee (Prather v. U.S., [1834] 9 App. D.C. 82).

Department of Justice, Criminal Tax Manual, section 10.4[1]: Failure to File, Supply Information, or Pay Tax

U.S. v. Bartrug, E.D.Va.1991, 777 F.Supp. 1290, affirmed 976 F.2d 727, certiorari denied 113 S.Ct. 1659, 507 U.S. 1010, 123 L.Ed.2d 278:

Federal income tax regulations governing filing of income tax returns do not require Office of Management and Budget control numbers because requirement to file tax return is mandated by statute, not by regulation.

[U.S. v. Bartrug, E.D.Va.1991, 777 F.Supp. 1290, affirmed 976 F.2d 727, certiorari denied 113 S.Ct. 1659, 507 U.S. 1010, 123 L.Ed.2d 278:]

44 U.S.C. §1505 Documents to be Published in the Federal Register

(a) Proclamations and Executive Orders; Documents Having General Applicability and Legal Effect [against persons living in states of the Union]; Documents Required To Be Published by Congress.

There shall be published in the Federal Register -

(1) Presidential proclamations and Executive orders, except those not having general applicability and legal effect or effective only against Federal agencies or persons in their capacity as officers, agents, or employees thereof;

(2) documents or classes of documents that the President may determine from time to time have general applicability and legal effect; and

(3) documents or classes of documents that may be required so to be published by Act of Congress.

For the purposes of this chapter every document or order which prescribes a penalty has general applicability and legal effect

26 C.F.R. § 601.702 Publication, public inspection, and specific requests for records.

(ii) Effect of failure to publish.

Except to the extent that a person has actual and timely notice of the terms of any matter referred to in paragraph (a)(1) of this section which is required to be published in the Federal Register, such person is not required in any manner to resort to, or be adversely affected by, such matter if it is not so published or is not incorporated by reference therein pursuant to paragraph (a)(2)(i) of this section. Thus, for example, any such matter which imposes an obligation and which is not so published or incorporated by reference shall not adversely change or affect a person's rights.