Keith King's wife Danielle was found to be having an affair for over a year

Adultery is a serious – and expensive – matter in the American state of North Carolina, as one man has discovered.

A court last week ordered Francisco Huizar to pay $8.8 million (£6.7 million) to Keith King, whose wife he had been seeing for more than a year.

Mr King, 48, a businessman, won his case for "alienation of affection" and “criminal conversation” based on centuries-old English common law.

“There isn’t a dollar amount that you can put on it for what I think my family’s worth,” he told the Inside Edition television show.

A Superior Court judge in Durham thought otherwise, awarding him $2.2 million in compensatory damages and $6.6 million in punitive damages.

View photos Francisco Huizar was told to pay $8.8 million in damages for adultery More

King married his wife, Danielle, in 2010. He said he discovered flirtatious texts sent to Huizar on her phone five years later.

At first he tried to keep his marriage together, for the sake their daughter, but then learned of the state’s adultery laws, he told the CNN affiliate WRAL.

"My marriage was murdered. It was destroyed," he said.

Most states have dropped the laws as archaic and for treating women as chattels, but they remain on the books in Hawaii, Mississippi, New Mexico, South Dakota and Utah as well as North Carolina.

A law firm in Raleigh said 200 claims were made in the state each year. Successful cases must show that plaintiff and spouse were happily married until the “malicious conduct of defendant was a cause of the loss and alienation of such love and affection”.

View photos Keith King exploited an arcane adultery law abolished in Britain in the 19th century More

“Criminal conversation” covers extramarital sexual acts – and was abolished in England and Wales in 1857.

However, Huizar’s attorney said the marriage was already in decline and that her client would appealing against the decision.

"My client became embroiled in a very unfortunate situation. He never sought to air the details of this situation in public," said Cheri Patrick in a statement. "The alienation of affections law in North Carolina is archaic, demeans the obligations of spouses in a marriage and should be stricken.

“Verdicts like these ignore the realities of how and why marriages fail and remove personal responsibility for a person's own marriage."