Southland (2009)

On Hood Day, a day where gangs seek retribution, LAPD is trying to keep the peace by camping out in neighborhoods prone to violence. Sammy and Ben leave their assigned neighborhood with disastrous results. Meanwhile, the neighborhood grabs a golden opportunity to seek a little retribution of their own against the gang banger who has been terrorizing them. Elsewhere, John and Jessica discover that another group of neighbors will go to any lengths to get a registered sex offender off their streets.