Filing a false affidavit is federal perjury, punishable by up to five years in prison and a fine as high as $250,000, and the penalty for filing a false affidavit rarely stops at the criminal sentence. The judge in the case where the affidavit was filed can throw it out, sanction the filer, order them to pay the other side’s legal fees, or dismiss the case outright. A conviction can end a professional license, strip firearm rights, disqualify a security clearance, and permanently block a noncitizen from naturalizing. It also becomes usable against the person’s credibility in any future court proceeding for at least a decade.
When an Affidavit Counts as False
Not every inaccuracy is criminal. To prove perjury, prosecutors have to show the signer “willfully” swore to a “material matter” they did not believe to be true.1Office of the Law Revision Counsel. 18 USC 1621 – Perjury Generally Two filters do most of the work.
Willfulness separates a bad memory from a crime. Misreading a pay stub and understating your income on a financial affidavit is not perjury. Deliberately understating it to lower a child support obligation is. Materiality is the second filter: the lie has to matter to the outcome. Falsely claiming $40,000 in income when you earned $80,000 changes the support calculation and is material. Misstating the color of your car in that same affidavit almost certainly is not.
You do not need a notary stamp for any of this to apply. Federal law gives an unsworn written declaration signed “under penalty of perjury” the same legal weight as a sworn affidavit.2Office of the Law Revision Counsel. 28 USC 1746 – Unsworn Declarations Under Penalty of Perjury Sign a document carrying that language and you are treated as if you raised your right hand in a courtroom.
Federal Criminal Penalties
Federal perjury is a felony. The statute authorizes up to five years in prison,1Office of the Law Revision Counsel. 18 USC 1621 – Perjury Generally which puts it in the Class D felony tier of the federal sentencing framework.3Office of the Law Revision Counsel. 18 USC 3559 – Sentencing Classification of Offenses
The fine ceiling is $250,000. Section 1621 says only “fined under this title,” but the general federal fine statute caps felony fines at that amount.4Office of the Law Revision Counsel. 18 USC 3571 – Sentence of Fine A court can impose prison, the fine, or both.
A separate statute, 18 U.S.C. § 1001, catches false statements made to any part of the federal government outside court proceedings. The maximum sentence is the same five years and the fine structure is similar.5Office of the Law Revision Counsel. 18 USC 1001 – Statements or Entries Generally Because § 1001 does not require a formal oath, it reaches false written statements submitted to federal agencies even when they are not styled as affidavits.
State Criminal Penalties
Every state criminalizes perjury, and most treat it as a felony. The specifics vary by jurisdiction, but the general pattern is multi-year prison exposure and fines typically starting around $10,000. Some states escalate penalties when the false affidavit is tied to a capital case or contributes to a wrongful conviction.
A state prosecution is separate from whatever happens in the case where the affidavit was filed. Someone can lose a custody dispute, be sanctioned by the family court judge, and then be charged criminally by a prosecutor. Those tracks stack rather than substitute for each other.
What the Judge in Your Case Can Do
Criminal charges take months. A judge who sees a false affidavit can act the same day, and these in-case consequences are often what hits a filer first.
- Strike the affidavit. The document is treated as never filed, and any ruling that relied on it may be revisited.
- Rule against the filer on the motion the affidavit supported. In serious cases the judge can dismiss the entire case or enter a default judgment for the other side.
- Order the filer to pay the opposing party’s attorney’s fees and costs. Under federal civil procedure, sanctions for filings that misrepresent facts can include the reasonable fees the other side incurred.6Legal Information Institute. Federal Rules of Civil Procedure Rule 11 – Signing Pleadings, Motions, and Other Papers
- Hold the filer in contempt. Federal courts have inherent authority to punish contempt by fine, imprisonment, or both, independent of any perjury prosecution.7Office of the Law Revision Counsel. 18 USC 401 – Power of Court
The quieter damage is credibility. A judge or jury that catches one lie starts questioning everything else the person has filed or said. In family court especially, where outcomes turn on the judge’s read of each parent’s honesty, a false affidavit can swing custody and support rulings sharply.
Getting Someone Else to Sign One
Signing the affidavit yourself is not the only way to be charged. Convincing, pressuring, or paying another person to swear to a false statement is a separate federal crime called subornation of perjury, and it carries the same five-year maximum and $250,000 fine as perjury itself.8Office of the Law Revision Counsel. 18 USC 1622 – Subornation of Perjury Most states have an equivalent. These schemes often come apart because the recruited signer becomes a witness to the recruitment.
Immigration Consequences for Noncitizens
For a noncitizen, a perjury conviction is among the most damaging convictions in federal immigration law. It is classified as an aggravated felony under the Immigration and Nationality Act and permanently bars the person from establishing the “good moral character” that naturalization requires.9U.S. Citizenship and Immigration Services. Permanent Bars to Good Moral Character This is a lifetime bar on becoming a U.S. citizen, not a waiting period.
An aggravated felony also makes a noncitizen deportable and cuts off most forms of relief from removal. Even without a conviction, giving false testimony under oath to obtain an immigration benefit is a separate conditional bar to good moral character.10U.S. Citizenship and Immigration Services. Conditional Bars for Acts in Statutory Period A lie in a sworn affidavit supporting a visa petition carries immigration consequences whether or not criminal charges are ever filed.
Lasting Consequences After the Sentence
Because perjury is a dishonesty crime, its effects reach into most areas of life that depend on being trusted.
Professional Licenses
Lawyers, doctors, nurses, accountants, real estate agents, and financial advisors all hold licenses conditioned on ethical conduct. A perjury conviction can lead to suspension or revocation of a professional license. For attorneys, a felony conviction involving dishonesty is typically grounds for disbarment.
Firearm Rights
Federal law bars anyone convicted of a crime punishable by more than a year in prison from possessing a firearm or ammunition.11Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts Every federal perjury conviction clears that threshold, and most state felony perjury convictions do too.
Security Clearances
A perjury conviction is essentially disqualifying for a federal security clearance. Clearance adjudicators evaluate whether a person can be trusted to follow rules and disclose risks honestly, and a record built on lying under oath cuts directly against that. Even a finding of dishonesty during a clearance investigation, short of a conviction, becomes part of the applicant’s permanent clearance history.
Credibility in Future Cases
Under the Federal Rules of Evidence, a prior conviction involving a dishonest act or false statement can be used against the person’s credibility if they testify in any future case. For crimes of dishonesty the evidence comes in automatically, with no balancing test for the judge to apply, and it remains usable for at least ten years after the conviction or release from confinement.12Legal Information Institute. Federal Rules of Evidence Rule 609 – Impeachment by Evidence of a Criminal Conviction Anyone who later testifies, serves as an expert witness, or signs sworn statements professionally carries that mark for a decade or longer.
Why Perjury Charges Are Still Relatively Rare
Perjury is notoriously hard to prosecute, which shapes how often the full penalty actually lands. Federal courts apply the two-witness rule: the government must prove the statement was false through at least two independent witnesses, or one witness supported by corroborating evidence.13Justia Law. Weiler v United States, 323 US 606 (1945) One person’s word against the affiant’s is not enough. Many states apply a similar corroboration requirement.
Taking back a false statement helps less than people expect. Under the main federal perjury statute, § 1621, recantation is not a defense at all; the crime is complete when the false statement is delivered. A separate statute covering false declarations in court and grand jury proceedings, § 1623, recognizes a limited recantation defense, but only if the person admits the falsehood during the same continuous proceeding, before it has substantially affected the outcome and before it becomes obvious the lie will be exposed.14Congressional Research Service. False Statements and Perjury – An Overview of Federal Criminal Law Confessing after being caught does not qualify.
The practical lesson is not that false affidavits are safe. It is that even in the many cases where no criminal charge is ever filed, the judge’s in-case powers, the licensing boards, the clearance adjudicators, and the immigration authorities still have everything they need to act.