“I’m coming home, I’ve done my time.” – Dawn, featuring Tony Orlando

You’d have to be thicker than the average cinderblock not to appreciate the logic behind the so-called Megan’s Law. If the kindly old grandfather who just moved in down the street was a sex offender with a history of preying on children, you’d surely want to know about it when he offered your son a few bucks to mow the grass or offered to watch your daughter while you ran to the market. More to the point, you’d have a right to know, wouldn’t you?

Maybe not. The Supreme Court is considering the question now – it heard arguments last week from convicted child molesters in two states who are challenging that right. The court probably won’t rule until summer. Meantime, we are left to chew on an exceptionally knotty moral and legal conundrum.

Megan’s Law is named for Megan Kanka, a 7-year-old New Jersey girl who was raped and murdered in 1994 by a neighbor. Nobody knew he was a convicted sex offender. Under this law, variations of which have since been enacted all over the country, child molesters and rapists who have served their sentences are required to periodically apprise police of their whereabouts and activities and provide updated photographs of themselves. In most states, Florida included, authorities must post the information on the Internet.

It is, in effect, a probation that never ends. The lawyers challenging the law call it “a modern-day scarlet letter.”

As such, it flies in the face of the notion, espoused in a hundred movies of the week and one corny old song about a yellow ribbon, that after one has paid one’s debt to society, one is entitled to a second chance, a clean slate. There is evidence that Megan’s Law may have led to extralegal sanction of those who have already served their time.

Consider a few headlines from recent years: A family in St. Cloud, Fla., loses its lease on its residence, reportedly for failing to disclose that one of its members was a pedophile.

A political consultant in Torrance, Calif., files suit because, he says, his business was ruined after letters detailing his history of child molestation were sent to his clients.

Residents in Fresno, Calif., gather outside the home of a sex offender and demand that he leave their neighborhood. A woman at the scene told a reporter the man should go back to jail. The problem, of course, is that he had already been in jail – and finished his sentence.

I’m not trying to get you to feel sorry for child molesters and rapists. Lord knows I don’t. I’m just making the argument made by civil libertarians who oppose Megan’s Law.

Now, here’s my argument: There is no sense in pretending that crimes of sexual predation, particularly against children, are like other crimes. They are not. It’s not just that these crimes are more heinous and the fears they raise in us more primal. It’s also that sex criminals are more prone to recidivism. Note that the woman in Fresno eventually got her wish. The offender was back in jail just a few years later – for another sex-related violation.

Note, too, that most of the information gathered and disseminated under these ordinances isn’t exactly secret. To the contrary, it’s a matter of public record. The only thing Megan’s Law does is make it more easily accessible to the general public.

This is not an incidental concern.

For me, as, I suspect, for most parents, any debate about the value of Megan’s Law inevitably comes down to very personal considerations. My child, my street.

If I had questions about some guy down the block who seemed to watch with too avid an interest as my daughter went bicycling by, I’d want to be able to get answers – not to harass, but to take appropriate precautions. And I’d want those answers sooner rather than later. And though the guardians of civil liberties raise some excellent points, I think that trumps every other consideration on the table.

Let’s hope the Supreme Court agrees.

Leonard Pitts Jr. is a columnist for the Miami Herald. His e-mail address is: lpitts@herald.com.