Most states make it a criminal offense (statutory rape) to have sexual intercourse with a person under the age of consent—which is usually between 16 and 18 years of age. These laws are premised on the belief that a person under the age of consent is not capable of giving informed consent to sexual intercourse—even if the person was a willing participant. Statutory rape may be prosecuted as a misdemeanor offense or as a felony offense—depending on the state’s laws and the ages and circumstances of the sexual activity.

But many states recognize a defense to such a criminal offense if the persons engaged in the sexual activity were close in age—within three years, for example—provided the persons were at least 14 years of age, for example. These laws are sometimes called Romeo-and-Juliet laws, and are usually located in a state’s statutes, in the penal or criminal code.

In New Hampshire, the age of consent is 16 years old, as per the state's statutory rape laws. This means that individuals under the age of 16 cannot legally give consent to sexual activity, and engaging in sexual intercourse with someone under this age may be prosecuted as statutory rape. New Hampshire does recognize a 'close-in-age' exemption, often referred to as a Romeo-and-Juliet law, which provides that individuals who are both above the age of 13 and within a specified age difference from each other (usually not more than 3 years) may legally engage in consensual sexual activity without it constituting statutory rape. However, the exact provisions and limitations of this exemption can vary, and it is important to consult the specific statutes or an attorney for detailed information. Additionally, the severity of the offense and whether it is charged as a misdemeanor or felony can depend on the ages of the individuals involved and the circumstances of the case.