Hit list: deadly sex offender registries.

ON EASTER Sunday, Stephen A. Marshall, a 20-year-old Cape Breton dishwasher visiting Maine, borrowed his father's truck, rifle, and two handguns, shot and killed two men in two different towns, then boarded a bus to Boston, where he was approached by police and shot himself. Marshall's motive for the murders is still unclear, but his method of selecting victims is not: He found them on Maine's online registry of sex offenders.

All 50 states and the District of Columbia maintain Web sites providing information on convicted sex offenders who have been released from prison. States differ in how much information they provide. Maine's registry provides users with home addresses, employment addresses, photos, and legal descriptions of the crimes that landed offenders on the registry.

The justification for maintaining such public lists rests on the presumption that sex offenders have higher recidivism rates than other criminals--though Bureau of Justice statistics indicate that rapists are substantially less likely than other violent and nonviolent criminals to be rearrested for the same crime. The psychological theory that pedophilia is a lifetime condition carries more weight with the public, but registries do not distinguish among varieties of sex offenders. As it happens, one of Marshall's victims, 24-year-old William Elliott, was registered for the crime of having sex, at the age of 19, with a girlfriend who was two weeks shy of her 16th birthday.

You can decide for yourself whether such a man deserved to be marked for life, let alone murdered. Meanwhile, the registries create a conundrum: If the offenders are still menaces to society, why have they been released from prison? And if they are not, why is the state blocking their attempts to return to society?