DETROIT (WWJ/AP) – A Detroit man has been ordered to pay $30,000 in back child support for his ex-girlfriend’s child — even though he’s not the father.

Carnell Alexander brought his case to Wayne County Circuit Court with hopes for a fix. Instead, Judge Kathleen McCarthy told him Tuesday he waited too long to challenge the situation and “failed to take this matter seriously.”

Alexander said the paternity case started in the 1980s when the woman gave his name to a case worker so she could get assistance for her baby, who was born in 1987.

The woman agrees that Alexander wasn’t the father and a DNA test taken in 2013 backs that up. But that wasn’t enough to sway McCarthy, who ruled that despite the case being decades old, Alexander still has to pay.

More challenges are planned. Alexander’s lawyer Cherika Harris said an arrest warrant due to unpaid child support has since been dropped.

“To continue to harass and burden him to pay for a child that is not his, when they know who the real father is now, I don’t understand this,” Harris told WXYZ-TV.

Alexander said he first learned he was considered a deadbeat dad during a traffic stop when an officer told him there was a warrant for his arrest.

He was accused of ignoring an earlier summons in the paternity case. Alexander said he was in prison when the process server appeared at his father’s home.

“I had no knowledge that I had a child support case against me,” he said.

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