26 USC 5762 - Criminal penalties

(a) Fraudulent offenses 
Whoever, with intent to defraud the United States
(1) Engaging in business unlawfully 
Engages in business as a manufacturer or importer of tobacco products or cigarette papers and tubes, or as an export warehouse proprietor, without filing the bond and obtaining the permit where required by this chapter or regulations thereunder; or
(2) Failing to furnish information or furnishing false information 
Fails to keep or make any record, return, report, or inventory, or keeps or makes any false or fraudulent record, return, report, or inventory, required by this chapter or regulations thereunder; or
(3) Refusing to pay or evading tax 
Refuses to pay any tax imposed by this chapter, or attempts in any manner to evade or defeat the tax or the payment thereof; or
(4) Removing tobacco products or cigarette papers or tubes unlawfully 
Removes, contrary to this chapter or regulations thereunder, any tobacco products or cigarette papers or tubes subject to tax under this chapter; or
(5) Purchasing, receiving, possessing, or selling tobacco products or cigarette papers or tubes unlawfully 
Violates any provision of section 5751 (a)(1) or (a)(2); or
(6) Destroying, obliterating, or detaching marks, labels, or notices before packages are emptied 
Violates any provision of section 5752;

shall, for each such offense, be fined not more than $10,000, or imprisoned not more than 5 years, or both.

(b) Other offenses 
Whoever, otherwise than as provided in subsection (a), violates any provision of this chapter, or of regulations prescribed thereunder, shall, for each such offense, be fined not more than $1,000, or imprisoned not more than 1 year, or both.