Criminals are everywhere. There’s simply no avoiding it. However, you can discover who some of the criminals are in neighborhoods near you. Websites like Family Watchdog allow you to type in your own address and see some of the potential threats. You can click on individuals to see their pictures and what crimes they have committed.
Note that registered sex offenders registries record only those who have been convicted. Also note the incredible difference in crimes. There is a big difference between multiple recent convictions of predatory sexual assault and an ancient conviction of indecent exposure.
Also note the incredible difference in the criminal density for a particular area. If you find the home you are about to buy is surrounded with registered sex offenders, there’s an even chance that it’s also surrounded with thieves and drug dealers too. Just something to think about.
Consider the difference between this map of Washington, DC and Capistrano Beach, CA.