Do Paternity Tests Always Get It Right?

Paternity tests are nearly universally presented as being definitive. Paternity testing is maintained to be a scientific process to deliver a clear yes-or-no answer to one of life’s most sensitive questions. The reality is that modern DNA tests generally do produce probability scores that typically exceed 99.9%. The apparent precision of DNA tests have made the process sting a cornerstone in different types legal disputes, particularly paternity cases.

Overview of How Modern Paternity Tests Work

Most contemporary paternity tests analyze what technically is known as short tandem repeats (STRs). These are highly variable regions of DNA. By way of explanation, a child inherits half of these markers from each biological parent. By comparing the child’s STR profile with that of the alleged or putative father, laboratories can determine whether the genetic inheritance of a child aligns with the purported father. When it does align, the probability of paternity can be calculated. If there is no such alignment, paternity can be excluded.

What Do DNA Test Accuracy Rates Really Mean?

We oftentimes hear or read that a paternity test has a 99.9% probability rating. A 99.9% probability does not mean absolute certainty. What it does mean is that, given the tested markers and population statistics, there is a 0.1% chance the conclusion in a particular test is incorrect. While this percentage is exceedingly small, that margin matters in high-stakes situations like paternity cases. Accuracy is contingent on a number of factors that include both correct sample handling and proper laboratory procedures.

Understanding the Role of Sample Collection

Errors most often arise not in the genetic analysis itself but in how samples are collected and handled. A variety of different types of errors occur with what some consider surprising regularity and include:

• Contamination
• Mislabeling
• Other mistakes and mix-ups with the propensity to compromise results

As an aside, at-home kits, while seemingly convenient, carry a higher risk of user error than professionally administered tests. Chain-of-custody procedures are crucial when results are used for legal purposes such a paternity proceeding in a New Jersey court.

Human Biology Isn’t Simplistic

It is also important to understand that there are biological phenomena that can complicate paternity testing. A primary example is a condition called chimerism. This is a condition in which one person has two different DNA profiles. Such a situation can lead to misleading results if the tested DNA doesn’t match the reproductive cells involved in conception.

Another example of biological complications are mutations in STR markers. These are not commonplace, but when they do occur, they can create discrepancies that require expert interpretation.

Importance of Testing All the Right People

Including the mother’s DNA in the analysis significantly improves accuracy. Without it, laboratories must infer which genetic markers came from the mother. This type of scenario increases result uncertainty. Testing close relatives of the alleged father instead of the father himself can also introduce ambiguity into the process.

Laboratory Standards and Quality Control

Not all laboratories are run equally. Accredited labs follow rigorous standards, participate in proficiency testing, and use validated methods. The stark reality is that errors are more likely when tests are conducted by unaccredited facilities. The same holds true when cost-cutting compromises quality at a particular lab. Choosing a reputable lab is as important as the test itself on many levels

Legal Versus Peace-of-Mind Testing

Legal paternity tests require strict documentation and witnessed sample collection. This is necessary in order to ensure admissibility in court. On the other hand, so-called peace-of-mind tests, often cheaper and more accessible, may be accurate scientifically but lack the procedural safeguards needed for legal validation in a New Mexico court of law. Confusing the two can lead to unexpected complications when paternity testing is being undertaken.

In conclusion, in the vast majority of cases, modern DNA tests undertaken for paternity purposes are highly reliable. When conducted by accredited laboratories, using properly collected samples and appropriate participants, they are among the most accurate tools in forensic science. As we discussed, rare biological anomalies, human error, and procedural shortcuts can lead to incorrect data in a particular DNA test. DNA science is strong. On the other hand, like all science, DNA testing works best when applied carefully, responsibly, and with an understanding of its limits.

If you have any questions or are in need of legal assistance, you can schedule a no cost, no obligation initial consultation by calling the Law Offices of Peter Van Aulen at 201-845-7400.