Although it's rarely enforced, it's a crime in New Hampshire to commit adultery. That could change if a bill that has already passed The House becomes a law.

Rep. Tim O'Flaherty, a Democrat from Manchester, sponsored the bill that would repeal the state statute, which calls for a Class B misdemeanor for those found guilty of adultery. The misdemeanor comes with a fine of up to $1,200.

O'Flaherty thinks the current law invades privacy.

"I don't think there's any appetite in New Hampshire to use police powers to enforce a marriage," O'Flaherty told members of the Senate Judiciary Committee during a public hearing March 25. 

The bill to repeal the law, which dates back to the early 1800s, passed the house 268-29 and it will face a vote by the Senate Thursday.

The law only applies to a case between a man and a woman and is defined as "intercourse from which spurious issue may arise" -- meaning a child born of the illicit affair. Same sex couples, according to the court, "cannot engage in the one act that constitutes adultery under the statute."

New Hampshire is one of 21 states that still consider adultery a crime. For instance, in Massachusetts, those who commit adultery could face up to three years in prison. In Rhode Island, a $500 fine is all one will face.

"It's not any kind of deterrence," O'Flaherty said of the law. "People are going to cheat on their spouses regardless of what the law is." 

But, they may have extra incentive to do so if the repeal of the New Hampshire statute occurs. Gov. Maggie Hassan will likely sign the repeal according to her spokesman.

Rep. Carol McGuire, a Republican from Epsom who has already tried a similar repeal of the adultery law in 2010, is co-sponsoring the 2014 version.

"I don't want to live in a place where the police are responsible for investigating adultery," McGuire said.