Everything else in tax enforcement is, in the end, about money — how much is owed, how it will be collected, what penalties attach. Criminal tax is about something different: liberty. When the government concludes that a tax problem was not a mistake but a willful crime, a separate body of law takes over, with a higher burden, a different agency, and consequences measured in years rather than dollars. This is the final piece of the enforcement picture, and the one where the cost of a misstep is greatest.
The principal offenses
Title 26 defines a compact set of tax crimes that prosecutors deploy — often several at once for the same conduct. Evasion under § 7201 is the flagship felony. Failure to file under § 7203 is the misdemeanor floor. Filing a false return under § 7206 is a felony built on perjury. Section 7202 reaches employers who fail to pay over withheld trust-fund taxes, and § 7212(a) — the “omnibus clause” — criminalizes corruptly obstructing the administration of the tax laws.
| Statute | The offense | Class | Max. prison |
|---|---|---|---|
| § 7201 | Attempt to evade or defeat tax | Felony | 5 years |
| § 7202 | Willful failure to collect or pay over tax (trust fund) | Felony | 5 years |
| § 7203 | Willful failure to file, pay, or keep records | Misdemeanor | 1 year |
| § 7206(1) | False return or statement under penalty of perjury | Felony | 3 years |
| § 7206(2) | Aiding or assisting a false return (reaches preparers) | Felony | 3 years |
| § 7212(a) | Corruptly obstructing tax administration (omnibus) | Felony | 3 years |
Evasion — § 7201
Tax evasion is the most serious tax crime and the government’s favored charge in a strong case. It has three elements, each of which must be proved beyond a reasonable doubt: a tax deficiency, an affirmative act of evasion, and willfulness. It comes in two flavors — evasion of assessment (hiding the liability before it is determined) and evasion of payment (concealing assets to defeat collection of a liability already owed). A conviction carries up to five years in prison per count.
The misdemeanor floor — § 7203
The line between the felony and the misdemeanor is the single most important distinction in criminal tax, and it turns on conduct. A mere omission — failing to file a return, or failing to pay — is the misdemeanor under § 7203, punishable by up to one year. Felony evasion requires something more: an affirmative act designed to mislead or conceal. As the Supreme Court explained in Spies v. United States, it is the positive act — a false return, a double set of books, hidden bank accounts, nominee entities, destroyed records, false statements to agents — that converts passive non-compliance into felony evasion.
False returns and perjury — § 7206
Section 7206(1) is, in substance, a perjury statute: it is a felony to willfully sign, under penalty of perjury, a return or document that the signer does not believe to be true and correct as to every material matter. Crucially, it does not require proof of a tax deficiency — the crime is the false statement itself, which makes it an easier charge for the government than evasion. Section 7206(2) reaches anyone who aids or assists in preparing a false return, and is the provision most often used against accountants and return preparers.
The omnibus clause — § 7212(a) and Marinello
Section 7212(a)’s “omnibus clause” makes it a felony to corruptly obstruct or impede the due administration of the tax laws. Read literally it is almost limitless, and for years the government used it broadly. The Supreme Court reined it in. In Marinello v. United States, 584 U.S. ___ (2018), the Court held that a conviction requires a nexus between the defendant’s conduct and a particular administrative proceeding — an audit, an investigation, or other targeted action — that was pending or reasonably foreseeable, and of which the defendant was aware. Routine non-compliance, untethered to a specific proceeding, is no longer enough.
Willfulness — the common thread
Every one of these crimes (except the omnibus clause, which requires “corrupt” intent) turns on willfulness, and the standard is favorable to defendants. Under Cheek v. United States, 498 U.S. 192 (1991), willfulness means the voluntary, intentional violation of a known legal duty: the government must prove the defendant knew the law imposed the duty and intentionally violated it. A genuine, good-faith misunderstanding of what the law requires — even an objectively unreasonable one — negates willfulness. What does not help is disagreement with the law’s validity; believing the income tax is unconstitutional is not a defense.
How the government builds a case
Criminal tax cases are investigated by the special agents of IRS Criminal Investigation, and they reach the courtroom along a recognizable path: a civil examination that develops firm indications of fraud (or an informant’s tip) is referred to CI; CI investigates, administratively or by grand jury; the case goes to the Tax Division of the Department of Justice for authorization; and from there to a U.S. Attorney for indictment. To prove the numbers, the government uses either the specific-items method (tracing particular unreported receipts) or, where records are missing, an indirect method — the net-worth method approved in Holland v. United States, 348 U.S. 121 (1954), or the bank-deposits and cash-expenditures methods.
The clock — § 6531
Criminal tax has its own statute of limitations. Under § 6531, the major tax offenses — evasion, filing a false return, and willful failure to file where evasion is involved — carry a six-year limitations period, longer than the general federal default. The period can be extended in defined circumstances, including when the defendant is outside the United States.
The civil-criminal interface — and the off-ramps
The dangerous ground is the seam between civil and criminal, the eggshell audit, where a civil examination can quietly become a criminal investigation. Three protections matter most there. Privilege: the attorney-client privilege and a properly structured Kovel engagement for the accountant — but not the limited § 7525 practitioner privilege, which does not reach criminal matters. The Fifth Amendment, which protects compelled testimony. And the voluntary disclosure practice — the IRS’s established path for a willful taxpayer to come forward and resolve the matter civilly — but only if it is done before the IRS is already on the trail. Once a matter is referred to the DOJ, § 7602(d) bars the IRS from using its civil summons power, a signal that the posture has changed.
The practical takeaway
Criminal tax is the sharp end of the enforcement system, and it runs on a logic opposite to the civil side: the government bears a heavy burden — willfulness beyond a reasonable doubt — but the cost of helping it meet that burden is catastrophic. The defense begins with recognizing the criminal posture early, preserving privilege and the Fifth Amendment, evaluating voluntary disclosure while the window is open, and never supplying the affirmative act or the false statement that turns a civil problem into a felony. When liberty is on the table, the first call is to counsel, and it should be made before the next conversation with the IRS, not after.