I was talking to my neighbor last fall when an unfamiliar man walked out of a house and stood in the driveway talking to a group of teens.

“Who’s that? A new neighbor?” I asked my neighbor. “Yes,” she replied as her kids kicked a ball around at her feet. “From what I’ve heard, he’s the boyfriend of the woman who lives there with her children. I hear he’s a sex offender. But if you look at the sex offender registry online, he won’t show up because he is registered at his real address in the town next door.”

I don’t have any children, but I convulsed. It was the week before Halloween and the neighborhood kids were already dancing around the street with angel wings and witch hats. I told my neighbor that I had just read an article about how parents could protect their kids by using their cell phones to track sexual predators. But based on what she had just told me, that wouldn’t help. This guy wouldn’t even show up on the registry–”at least not accurately.

The Chicago Reporter has now stumbled upon something even more troubling, finding that hundreds of child sex offenders in Chicago are listed on the child sex offender registry but at addresses that violate state law.

We’ve all heard stories of sex offenders living too close to schools who are violating Illinois’ 500-foot law. But many people don’t know that it’s also illegal in Illinois for child sex offenders to live that close to child care facilities.

The percentage of sex offenders living near child care facilities is far greater than the percentage of sex offenders and predators living illegally near schools and parks.

Reporter Jeff Kelly Lowenstein has found that 44 percent of the offenders who local authorities say are “compliant” are in violation of state law concerning child care facilities. And we’re not just talking about sexual predators living within a few blocks of a day care. Kelly Lowenstein has found examples in Chicago where convicted child sex offenders are living on the same block, next door and, in one case, in the same building.

Obviously, everybody has to have some place to live. And some people argue that 500-foot boundaries are ineffective–”that many child sex offenders are family members living at a kid’s own home. So I’m not arguing whether we should or should not have a 500-foot boundary. But the bottom line is that it is our state’s law. It’s on the books. And apparently there are hundreds of people not following the rules, and local and state police aren’t stopping it.

The Illinois State Police tracks the addresses where these sex offenders live. But Kelly Lowenstein found that not only are there plenty of violators, but also that this information is not available on the state police’s website. If you were to plop in their address, you could see the number of offenders in their neighborhood. You can add to your search icons for schools and parks, which are also off limits. But no option is available for child care centers. And we only included the licensed child care centers that are part of the list of licensed child care centers kept by the Illinois Department of Children and Family Services. There are likely plenty more unlicensed home day-care facilities that are not included.

If we’re going to have laws on the books, we must follow them.