I have registered with this site and when there is a sex crime, I get an email.
I used it to determine where all the busts have been. For example, I type in a address where a couple hotels are here, and I might see multiple busts in a day, so I assume its UC. The data on the site only goes back 6 months. But that is only if the agency sends the data to this site. Where I live they do.
I also use the County Sheriff's website, here they publish all arrests every day, and you see their names and charges.