Washington ? In the eight years since 7-year-old Megan Kanka was raped and murdered by a paroled pedophile who lived across the street, all 50 states have adopted laws designed to let neighbors know when sex offenders live in their midst.

Wednesday, the Supreme Court will enter the debate for the first time, hearing arguments in cases from Alaska and Connecticut that challenge different elements of Megan’s Law.

The Connecticut case asks whether that state violates the Constitution by placing all sex offenders on an Internet registry without first providing a hearing to determine whether they still pose a danger. The appeal from Alaska questions whether those who completed prison sentences before the state passed its version of the law must be included in a registry.

Neither case attacks the core premise of the law, which requires those convicted of sex crimes to inform authorities of their whereabouts and mandate that local governments inform communities when a convicted sex criminal moves in. Lower federal courts have held Megan’s Law constitutional, and the Supreme Court has declined to hear appeals in those cases.