Los Angeles started doing this back in the 1980s, but several more cities have started suing gang members in an attempt to thwart potential violence.
L.A. now has 33 permanent injunctions involving 50 gangs --- and the people involved don't get to do anything fun. From the AP story:
Among other complaints mentioned in the story, critics say these kinds of efforts violate people's civil liberties.
In this photo from the AP, Fort Worth Police Gang Unit officers patrolling an area frequented by gang members arrest Edward Palacios, who they say is a known member, after he's found to have outstanding arrest warrants.

