The High Court has recently handed down an important decision highlighting the significant role DNA evidence can play in resolving disputes about parentage.
In Re YZ (Declaration of Parentage: BATUK: DNA Evidence) [2026] EWHC 1601 (Fam), the court was asked to determine whether a British serviceman was the biological father of a child born in Kenya. Despite the father’s repeated denials, the court ultimately found that the DNA evidence, together with the wider evidence in the case, proved that he was the child’s father.
The background
The child’s mother said she had been in a relationship with a British soldier serving with the British Army Training Unit Kenya (BATUK). She explained that the relationship resulted in the birth of her son, but that after discovering the soldier had a partner in the UK, communication broke down.
When she later sought assistance in establishing paternity, her attempts were unsuccessful, leaving her with little option but to ask the English court to make a formal declaration of parentage.
The importance of DNA evidence
As part of the proceedings, the court directed that DNA testing should take place.
The results were striking. Genetic analysis concluded that the DNA evidence was more than one billion times more likely if the alleged father was the child’s biological father than if the father were an unrelated man of East African heritage. This translated to a probability of paternity of over 99.9999999%.
Despite these results, the alleged father continued to deny paternity.
The father’s challenges
Rather than accepting the scientific evidence, the father argued that there could have been errors in the testing process. He questioned:
- whether the sample tested was actually his;
- whether samples may have been incorrectly labelled;
- whether mistakes could have occurred during storage or transportation; and
- aspects of the ancestry analysis used during the investigation.
He also initially denied ever having had any relationship with the child’s mother.
However, after the mother produced a photograph showing them together, he accepted that they had met, although he continued to deny having had a sexual relationship with her.
What did the court decide?
Mr Justice Poole carefully examined both the scientific evidence and the witnesses’ credibility.
The court concluded that there was no evidence whatsoever that the DNA samples had been mixed up or mishandled. The judge described the father’s arguments as having no real merit.
More significantly, the judge found that the father’s account changed as new evidence emerged and concluded that he had deliberately misled the court in an attempt to avoid a finding of paternity.
By contrast, the judge found the mother’s evidence to be honest, consistent and credible.
The court therefore made a declaration that the alleged father was, without hesitation, the child’s biological father.
Why does this matter?
This case is a reminder that where parentage is disputed, the court has the power under section 55A of the Family Law Act 1986 to determine the issue and, where appropriate, make a formal declaration of parentage.
It also demonstrates the considerable weight that the courts place on properly obtained DNA evidence. While parties are entitled to challenge expert evidence where there are genuine concerns, unsupported speculation about testing errors is unlikely to succeed.
Importantly, the court will not look at DNA evidence in isolation. It will also assess the credibility of each witness, the consistency of their evidence and whether they have been truthful throughout the proceedings.
Why a declaration of parentage matters
A declaration of parentage is about far more than biology.
For a child, it can provide certainty about their identity and legal parentage. It may also have wider implications for issues such as financial support, inheritance, nationality and future family relationships.
For parents, obtaining clarity can provide an important foundation for resolving other matters concerning the child.
How we can help
Questions about parentage can be emotionally difficult and legally complex, particularly where one parent disputes the facts.
If you are seeking to establish paternity, or if you have been asked to respond to an application for a declaration of parentage, obtaining early specialist legal advice can make a significant difference.
Our family law team can guide you through the process with clear, practical advice while keeping the welfare of the child at the centre of every decision.
Emma Sanders is a Partner at Just Family Law. If you would like to book an appointment with Emma to discuss your situation, please contact her at emmasanders@just-family-law.