Determining the father of a child is important for many reasons, among them the fact that it helps to establish certain legal rights and responsibilities After all, paternity determines who is responsible for supporting the child, who may have a hand in the child’s upbringing.

Once paternity is legally established, the mother and child are also granted access to the father’s medical history and genetic information in order to learn of any medical problems the child may inherit. A suit to challenge paternity isn't always something that's initiated by the mother. Sometimes a court or medical professional names the wrong person as the father of a child, or lab tests can provide erroneous results. In those cases, either parent may file a suit challenging paternity.

Grounds for Challenging Paternity

Many paternity proceedings rely on medical evidence to show who the father is. Usually these tests are accurate, but sometimes they produce erroneous results. The following are grounds for challenging a prior finding of paternity:

• Tainted lab results (e.g., evidence of prior errors in lab results and routinely substandard work);
• Fraudulent lab results (e.g., evidence that the opposing party sent someone else to take the lab test on his behalf);
• Proof of infertility or sterility;
• Proof that test results were tampered with; and
• Proof of the mother’s infidelity in marriage -- when a child is born into an opposite-sex marriage, the husband is presumed to be the father unless proven otherwise.

State laws vary from state to state as to the grounds they accept to challenge a paternity test.

How to Challenge Paternity

A suit to challenge paternity is very similar to one establishing paternity. Each state has a slightly different way of starting a lawsuit, so check with a local family law attorney or with your state’s family law courts to find out exactly how to begin.

Some states will take into consideration how many years have passed with a child believing a certain man is their father, and make disproving paternity more difficult because of the emotional and psychological effects it may have on the child.

Usually, the first step is to file a complaint with the court. Once the complaint is filed, the court may order one or more DNA tests for the father and the child, and seek evidence from other sources to determine the actual father. This other evidence may include medical documents discrediting paternity or if the true father decides to voluntarily acknowledge paternity. Blood tests may also be used to help determine whether the alleged father is biologically related to the child, but blood tests alone don't determine who the father actually is. However, DNA tests are the most accurate way of determining paternity.

At the end of the process, the court will issue an order naming the father. The parents must then meet to determine child support and custody arrangements.

Need Legal Help Challenging Paternity?

With paternity comes a long and important list of legal responsibilities, justifiably so. However, for any of those responsibilities to apply, there must be a fair process in which to determine paternity. That process must rely on sufficient evidence, but as you can see there are times when evidence relied on by the courts can be tainted. Reach out to an experienced family law attorney who will be in the best position to evaluate and challenge any evidence in a paternity case.