California Paternity Law

Why Establishing Parentage Matters in California

The Difference Between Biological and Legal Parentage

California law draws an important distinction between a biological connection and legal parentage. A biological parent contributes genetic material, but a legal parent is the person the law recognizes as having enforceable rights and responsibilities toward the child.

That distinction matters because legal parentage can exist even where there is no genetic connection, and a biological connection alone does not always create legal rights. Depending on the facts, a person may become a legal parent through a marital presumption, a valid declaration of parentage, presumed-parent status based on conduct, adoption, or a court judgment. Until parentage is legally established or recognized, rights involving custody, visitation, decision-making, and support may remain uncertain.

The Benefits of Legal Parentage

Establishing parentage provides security for all parties involved:

• For a Legal Parent: It provides standing to request child custody and visitation orders (Cal. Fam. Code § 3010), and to participate in major decisions about the child’s health, education, and welfare.
• For the Other Parent or Caregiver: It creates a legal basis to seek enforceable child support and to allocate uninsured medical costs, childcare expenses, and other responsibilities (Cal. Fam. Code § 3900).
• For the Child: It can secure inheritance rights, access to relevant family medical history, and eligibility for dependent benefits such as Social Security or Veterans benefits.

The Parentage Process: From Petition to Final Judgment

Step 1: Filing and Service

The process typically begins when a Petition to Establish Parental Relationship is filed in the Superior Court of the county where the child resides.

• Standing: The action can be brought by the mother, the alleged father, the child (through a guardian ad litem), or the local child support agency (Cal. Fam. Code § 7630).
• Service: The person filing the petition must formally “serve” the other parent with the papers, giving them distinct notice and an opportunity to respond.

Step 2: Genetic Testing (DNA)

If parentage is contested, the court will order genetic testing.

• Accreditation: This is not a drugstore kit. Testing must be performed by a laboratory accredited by the relationship testing body approved by the United States Secretary of Health and Human Services.
• The Threshold: Under California law, if the paternity index (the statistical probability) is 100 or greater, it creates a rebuttable presumption that the alleged father is the biological father (Cal. Fam. Code § 7555).

Step 3: The Final Judgment and Parenting Plan

Once parentage is confirmed—either through voluntary admission or DNA results—the court issues a Judgment of Parentage.

This judgment is often the foundation for a Parenting Plan. The plan addresses physical custody, parenting time, and legal custody. Without that next step, even a legally recognized parent may still lack a clear, enforceable schedule or decision-making framework.

Rights and Responsibilities After Parentage Is Established

Time-Sharing and Visitation

California public policy encourages frequent and continuing contact with both parents when that arrangement is in the child’s best interest (Cal. Fam. Code § 3020). Once parentage is established, the court may determine a time-share arrangement that affects both parenting time and child support.

If a father has been absent for a significant period, the court may order a “step-up” plan. This gradually increases visitation time as the child becomes comfortable, rather than forcing immediate overnight stays.

Financial Obligations

Both parents have an equal responsibility to support their child.

• Guideline Support: California uses a complex formula to calculate “guideline” child support, primarily based on each parent’s net disposable income and the percentage of time they spend with the child (Cal. Fam. Code § 4055).
• Retroactive Support: In an initial parentage action, the court has the discretion to order child support retroactive to the date the petition was filed. In some specific instances involving public assistance reimbursement, the state may seek reimbursement for up to three years prior to the filing.
• Birth Expenses: Depending on the circumstances, the judgment may also allocate reasonable expenses related to pregnancy and childbirth (Cal. Fam. Code § 7637).