When 7-year-old Megan Kanka disappeared from her quiet suburban New Jersey neighborhood in July 1994, no one knew that a twice-convicted child molester lived across the street.
After the man confessed to raping and murdering Megan, state lawmakers responded by empowering residents throughout the state to ascertain where convicted sex offenders lived. It is called Megan's Law, and versions of it have since been adopted by the federal government and all 50 states.
While the law's purpose is to help parents protect their children, critics say they violate sex offenders' constitutional rights.
The US Supreme Court Wednesday is set to take a close look at versions of Megan's Laws in Alaska and Connecticut to determine whether they strike the proper constitutional balance between community safety and the rights of convicted sex offenders who have completed their punishments.
The two cases, being heard back-to-back, are among the most important of the high court's current term. They touch on an emotional issue being followed closely by law enforcement officials, civil libertarians, and parents.
To critics, the registration laws resemble the Puritans' practice of publicly shaming wrongdoers by forcing adulteresses, for example, to wear a scarlet "A."
To supporters, the measures offer a tool to parents to protect their children from those who would prey on them.
In the Alaska case, Smith v. Doe, the high court will consider whether that state's sexual-offender registration law violates the constitutional ban on "ex post facto" laws that increase the punishment for an offense after the prior existing punishment for that same offense has already been served.
In the Connecticut case, Connecticut Department of Public Safety v. Doe, the justices will examine whether those listed on the state's sexual-offender registry are constitutionally entitled to an individualized determination of their current danger to the community before being listed.
"This case [Connecticut] is about publicly branding each respondent a 'Registered Sex Offender' ..., conveying the message to the public that he poses a continuing danger to public safety," says Shelley Sadin in her brief to the court challenging the law.
Ms. Sadin says Connecticut is altering the legal rights and status of sex offenders without offering them an opportunity to disprove the charge that they are dangerous.
Not everyone on the list will commit another crime or continue to be dangerous in the future, she says.
Connecticut Attorney General Richard Blumenthal, who is arguing his state's case before the high court, says the sexual-offender list is an accurate reflection of court records. He says release of those public records to members of the public does not suddenly entitle convicted sex offenders to a new level of rights.
"Every person on the registry has been convicted of an offense that is extraordinarily serious after a full and fair proceeding," Mr. Blumenthal says. "There is no constitutional requirement that distinctions be made between them based on predictions of dangerousness."
The state attorney general acknowledges that being listed on the registry will likely have a negative impact on an individual's reputation in the community. But he says that's not the state's fault.
"The stigma was created by the convicted sex offender who committed the crime and it is in no way defamatory or branding because it is simply truthful, accurate information."
There are basically two kinds of Megan's Laws, legal experts say. In some states, like New Jersey which passed the first such law, the state makes a determination about future dangerousness before including a sex offender on the list. Roughly half the states follow this model.
Other states, including Connecticut and Alaska, make no individualized determination of dangerousness. They simply list all convicted sex offenders and leave it to members of the public to draw their own conclusions.
Critics say such a system is unfair and counterproductive. "They don't give these people hearings to sort out who are the pedophiles, who are the dangerous ones," says Samia Fam, who filed a friend-of-the-court brief on behalf of the District of Columbia. "It can have a devastating effect on people's lives."
Jill Levenson, a board member of the Association for the Treatment of Sexual Abusers, says sexual-offender watch lists would be more effective if states identified those who were most likely to commit sex crimes in the future.
"Viewing everybody as the same actually dilutes the ability of the public to protect themselves from those who are most dangerous," she says.
Ms. Levenson says recidivism rates among sex offenders vary widely according to the crime. Those involved in incestuous assaults reoffend at rates of 6 to 10 percent, repeat rapists at 39 percent, and predatory pedophiles at 52 percent, according to Levenson.
Despite such well-documented research, some officials say they prefer an all-inclusive approach to provide parents as much warning as possible.
"All the experts in the world may not succeed in predicting what any given individual may do," Blumenthal says.
An individualized system can also be expensive and cumbersome, some legal experts say. "The District of Columbia had one of those (individualized) laws and it was so complex to administer no one was ever listed. It certainly was not that there were no sex offenders who needed listing," says Edward Schwab, an appeals court lawyer in the Office of the Corporation Counsel in Washington, D.C.
In the Alaska case the justices must decide whether applying the law retroactively to sex offenders is an effort by the state to regulate or to punish. If the law is deemed punitive, it must be struck down.
"Legally speaking they have done their time and were discharged from their sentence. They should be treated just like you or me," says Ms. Fam.
John Roberts, a Washington, D.C., lawyer representing Alaska, says the law is aimed at protecting the public from future harm rather than punishing sex offenders after their sentences have been served.
"The Alaska Sex Offender Registration Act is not excessive in comparison to its regulatory purposes, particularly when compared to more onerous laws the court has upheld in the past," Mr. Roberts says in his brief.