New Jersey passed the first "Megan's Law" in 1994 after the rape and murder of Megan Kanka by a previously convicted child sex offender who was living in her neighborhood. The law reflects the belief that every parent should have the right to know if a previously convicted and potentially dangerous sexual offender moves into their neighborhood.
Under Megan's Laws, child sex offenders, as defined by the law, are required to notify their local law enforcement agency of their current address and any changes in their address after release from incarceration. Depending upon the state and severity of the crime, they may be required to provide this information to law enforcement for life or for a certain period of time but usually for at least ten years. In some jurisdictions the law only applies to child sex offenders while others have a reporting requirement for other types of sexual offenders also.
A federal version of Megan's Law was enacted in 1996 as an amendment to the Jacob Wetterling Crimes Against Children's Act. The act requires all states to implement procedures to track certain types of convicted sexual offenders and provide reasonable methods of notifying concerned citizens when such persons reside in their neighborhoods.