An Oklahoma man is being forced to pay child support for another man's child because he ordered a paternity test too late.

Thomas, who did not give his last name, asked for a paternity test for his three year old son when his marriage fell apart.

He and his ex wife married after she got pregnant in high school. Thomas said at the time he had no reason to assume the baby was not his.

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On the hook: Thomas, pictured, is being forced to pay child support for his ex-wife's baby with her lover because he failed to order a paternity test within two years of the birth

Realization: Thomas took a paternity test twice proving he was absolutely not the father when the child was three

When the couple's marriage fell apart around the time the baby turned three, something led Thomas to ask for a paternity test.

He took the test twice and both showed he was absolutely not the father. But it did not matter because in Oklahoma a man has to question paternity within two years. Legally, the non-biological child he was raising was his.

Thomas said: 'I wish I was telling a lie. I wish it wasn’t the truth but it is.'

'That’s what makes it so crazy. Everyone I talk to about this can’t believe where the court system is coming from.'

News On 6 reports a judge initially ruled in favor of Thomas. But after revisiting the law, the judge ordered the duped dad to pay $500 per month in child support plus $15,000 in back support plus interest.

Thomas was in shock that the child he raised for three years was not his biological child

While Thomas is working to change the law, he accepts his fate.

However, he thinks DNA should be a determining factor for whether or not a man must pay child support rather than the child's age.

He told the station: 'At this point, there's really nothing I can do to get out of the $15,000 or get out of the child support, it's done, it's the law.'

According to the Oklahoma law, the child's mother and biological father could decide to let Thomas off the hook. But without their approval Thomas will be liable for child support for the next 15 years.