How to Disestablish Paternity and Fight Paternity Fraud in California: Timelines & Costs

Discovering that you might not be the biological father of a child you have been raising is an emotionally overwhelming experience. In California, dealing with paternity fraud is not just a personal matter; it is a complex legal issue with extremely strict deadlines. Whether you reside in Los Angeles, San Diego, or Sacramento, the state has rigid rules about when and how a man can legally disestablish paternity. If you miss the legal window, you could be held financially responsible for child support until the child reaches adulthood, regardless of biology. This guide will walk you through the procedures for challenging paternity in California. Keep in mind that family law is complicated, and you can always find an experienced, local family law attorney in our directory to help you navigate this difficult journey.

Step-by-Step Process to Disestablish Paternity in California

Challenging paternity requires filing the correct paperwork with the local court system and presenting compelling evidence. Here is a breakdown of how the process generally works in a California Superior Court.

Step 1: Determine Your Legal Status (Married vs. Unmarried)

Your legal strategy depends heavily on your relationship with the mother at the time of birth. Under California law, if you were married to the mother and living together when the child was conceived or born, you are legally considered the "presumed father." If you were not married, you likely became the legal father by signing a Voluntary Declaration of Parentage (VDP) at the hospital. The steps to undo these two situations are different.

Step 2: Filing the Correct Petition

To begin the process, you must file formal paperwork at the Superior Court of California, County of Los Angeles, Los Angeles, Superior Court of California, County of San Diego, San Diego, or Superior Court of California, County of San Francisco, San Francisco, or whichever county court has jurisdiction over the child. You will typically need to file Form FL-220, California, Judicial Council, Response to Petition to Determine Parental Relationship (Uniform Parentage) if the mother or the state has initiated a case against you, or Form FL-200, California, Judicial Council, Petition to Determine Parental Relationship to open a new case yourself.

Step 3: Requesting a Court-Ordered DNA Test

A home DNA test from a pharmacy is generally not admissible in a California court. You must file a motion asking the judge to order a formal, legally admissible genetic test. Under Cal. Fam. Code § 7551, the court has the authority to order the mother, child, and alleged father to submit to genetic testing at an approved laboratory.

Step 4: Filing a Motion to Set Aside the VDP

If you are an unmarried father who signed a VDP registered with the California Department of Child Support Services, Rancho Cordova, and you discover the mother lied about your biological connection, you must file a specific motion to set aside the declaration. You will need to file Form FL-280, California, Judicial Council, Request for Hearing and Application to Cancel (Set Aside) Voluntary Declaration of Parentage and prove to the judge under Cal. Fam. Code § 7576(a) that your signature was obtained through fraud, duress, or a material mistake of fact.

The Strict 2-Year Statute of Limitations

This is the most critical aspect of California paternity law. If you are a presumed father (married to the mother), Cal. Fam. Code § 7541 generally imposes a rigid two-year statute of limitations to challenge paternity. This means you must file your motion for blood or genetic testing within exactly two years of the child's date of birth. If you miss this deadline, the court may strictly enforce the conclusive marital presumption, meaning you will legally remain the father forever, even if a later DNA test proves you are not biologically related. Similarly, unmarried fathers who signed a VDP face an equally rigid deadline under Cal. Fam. Code § 7576(a): any legal proceeding to challenge and set aside the declaration on the basis of fraud, duress, or material mistake of fact must be commenced not later than two years after the effective date of the voluntary declaration (the date the form was registered with the Department of Child Support Services), rather than from the date of discovering the fraud. If you miss this two-year preclusive window, the court will dismiss the challenge as untimely, leaving your legal parentage intact.

How Much Does it Cost in California?

Disestablishing paternity involves court fees, mandatory testing costs, and typically legal representation. Here is a general breakdown of what you might expect to pay in California.

How Long Does the Process Take?

The timeline heavily depends on the county court's schedule and whether the mother contests your petition. In relatively straightforward cases where all parties agree to the DNA test, the process might take 3 to 6 months. If the mother fights the petition, refuses to cooperate with the genetic testing, or if there are complex arguments about the best interest of the child, the litigation can stretch out for 8 to 18 months in a California Superior Court.

Frequently Asked Questions (FAQ)