When a Father Lies in a Custody Case, Will He Be in Trouble? What Happens When Any Parent Lies to the Court

Last reviewed: October 5, 2026. This article is general information, not legal advice. Perjury, sanctions and custody rules differ by state, so check your state's statutes and speak to a family lawyer about your case.

Few things feel as unfair as hearing the other parent say something untrue about you in a custody case. If you've searched "when a father lies in a custody case, will he be in trouble", the honest answer applies to every parent, father or mother: the law treats a lie the same way whoever tells it.

Short answer: yes, a parent who lies in a custody case can be in real trouble. Lying under oath or in a sworn declaration can be perjury, a crime in every state. More often, the practical consequence is in the family case itself: the judge stops believing that parent, which can affect custody, and some states allow money sanctions for knowingly false abuse accusations. But the court has to see proof of the lie, so your job is to show it calmly with evidence.

Four ways a lie can backfire

1. Criminal perjury

Perjury generally requires a statement that is made under oath (or under penalty of perjury), is about a material fact, and is knowingly false. Exaggeration, faulty memory and differences of opinion usually don't meet that bar. Whether to charge someone is up to the prosecutor, and perjury prosecutions arising from custody cases are relatively uncommon. For comparison, the federal perjury statute, 18 U.S.C. § 1621, carries up to five years in prison, but custody cases are heard in state courts under state law.

2. Lost credibility with the judge

This is the consequence that matters most in practice. Custody cases often come down to whose account the judge believes. Once a parent has been caught in a clear lie, the judge is entitled to doubt the rest of their testimony too. That can tip contested issues, such as who has been doing the day-to-day parenting, in the other parent's favor.

3. Sanctions and legal fees

Some states let courts order a parent to pay money for bad-faith conduct. California's Family Code § 3027.1 is a specific example for knowingly false child-abuse accusations: the court can order sanctions up to the accused parent's costs of defending the accusation, plus attorney's fees for recovering them. Section 3027.1(c) says this remedy is in addition to other remedies available under the law.

4. A worse custody outcome

Courts decide custody based on the child's best interest. A parent who is willing to lie to the court, or to make up allegations against the other parent, may be seen as putting their own goals ahead of the child, or as willing to damage the child's relationship with the other parent. Many states' best-interest factors cover exactly that. Maryland's, for example, in Family Law § 9-201, include protecting the child from the negative effects of the parents' conflict (see our guide on how custody is decided in Maryland). Our best interest of the child checklist goes through common factors.

California also has a specific rule: under Family Code § 3022.5, a parent's motion to reconsider a custody order must be granted if it is based on the other parent having been convicted of a crime for falsely accusing them of child abuse.

False allegations of abuse: a careful distinction

Allegations of abuse are taken seriously, and courts must investigate them. That protects children. It also means the law draws a clear line:

• A knowingly false allegation, one the parent knew was untrue when they made it, can lead to sanctions, a worse custody outcome and, in some cases, criminal charges.
• A good-faith report that can't be proven is not a lie. Courts and child-protection agencies need parents to report real concerns, and many cases simply don't produce enough evidence either way.

If you've been falsely accused, cooperate fully with any investigation, follow every temporary order (including supervised visits if ordered), and let the evidence speak.

How to respond if the other parent lies

1. Don't respond with anger or a lie of your own. Shouting "that's a lie!" in court hurts you. Our article on what not to say in divorce court applies to custody hearings too.
2. Write down each false statement, when it was made and whether it was under oath (testimony, a declaration, a financial statement).
3. Gather evidence that contradicts it: messages, emails, photos, school and medical records, calendars, receipts, and names of neutral witnesses such as teachers or coaches.
4. Share it with your lawyer, who can use it in cross-examination, in your own declaration, or with a custody evaluator or guardian ad litem.
5. Ask about remedies in your state, such as sanctions, fee awards or, where justified, a modification of custody.
6. Keep the children out of it. Don't discuss the case or the other parent's honesty with them.

And if you've said something untrue yourself

If you realize you made a mistake or overstated something in a declaration or testimony, tell your lawyer straight away. Correcting the record quickly is far better than being caught later.

Sources

• California Penal Code § 118 (perjury defined): California Legislative Information
• California Penal Code § 126 (punishment for perjury): California Legislative Information
• California Family Code § 3027.1 (sanctions for knowingly false child-abuse accusations): California Legislative Information
• California Family Code § 3022.5 (reconsideration after conviction for false accusation): California Legislative Information
• 18 U.S.C. § 1621 (federal perjury statute): Cornell LII
• Md. Code, Family Law § 9-201 (best-interest factors, including protection from parental conflict): Maryland General Assembly