It's a well documented trend that criminals in jail for committing more serious crimes, especially the sociopaths and murderers, are generally of higher average individual intelligence (as measured by things like IQ tests) compared with the local population in which they live. And that's just the criminals that get convicted. (Although street crime, on the other hand, tends to have bellow-average IQ perpetrators.)

Studies have also found that areas with populations of lower average intelligence tend to have more crime, but that's a very different statement entirely.