ALBUQUERQUE, N.M. (WHAT THE TECH?) — Do you know everyone who lives in every house in the neighborhood where your kids will be trick or treating? Probably not.

If you knew there was a convicted sex offender living in that neighborhood, you wouldn’t want them knocking on their door.

How do you find out where they live?

The Department of Justice makes that information available on a public website. It is nsopw.gov.

The department renamed the registry in honor of the memory of 22-year-old Dru Sjodin. Sjodin was abducted and killed in 2003.

The website is the complete registry of every convicted sex offender.

The information is compiled from state databases of local law enforcement agencies across the country.

There’s also a smartphone app, NSOPW for iPhone and Android.

The app uses your location to show a map of the area and where registered sex offenders live.

Zoom in on a neighborhood where your kids will be trick-or-treating. The map lists each registered sex offender along with a map showing their address and their mugshot. By clicking or tapping on the residence or name, you can see the offense, criminal history, last reported employer, a description of their vehicle, any distinguishable features such as tattoos, and scars, and any aliases they use.

The sheer number of convicted sex offenders in the registry may shock you. At last count, the Justice Department said there were nearly 780,000 sex offenders.

The sex offender registry is good information for parents to know.

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