Street gangs have existed in San Luis Obispo County since the 1960s.
The county has been historically populated by Sureño-related gangs, an umbrella term that describes loosely affiliated members who trace their origins to Southern California, according to a March report on transnational gangs published by the California Department of Justice.
Sureños — meaning “Southerners” —are historically aligned with the Mexican Mafia prison gang, an association of convicts within the U.S. prison system formed in the 1950s in California to protect themselves from other prison gangs.
Members of these Sureño groups, though they share the same alliance, will often fight among themselves over control of certain areas or for other reasons, said Sgt. Keith Scott, head of the county Sheriff’s Office Gang Task Force.
Norteños — or “Northerners” — are aligned with the Nuestra Familia prison gang and historically have operated from Monterey, Kings and Tulare counties northward through Washington state, with some members in San Luis Obispo County.
Nuestra Familia traces its roots to Folsom and Soledad Correctional Training Facilities in Sacramento and Monterey counties in the 1960s, formed to protect Mexican American prison inmates who came from rural Northern California from rival Southerners.
Scott said Northern gangs typically do not fight among themselves. They are more organized and violent and will fight Southerners for just about anything, he said.
San Luis Obispo County is sandwiched between the historical turf of these two rival factions.
“We’re a dividing line,” Sheriff Ian Parkinson said.
The California Department of Justice report states that San Luis Obispo County has a Mexico-based criminal presence in drug trafficking and outdoor marijuana grow activity. The report states that the Sinaloa cartel — thought to be the most powerful of Mexican cartels — is particularly active in Southern California, where it coordinates with Sureño street gangs.
The northern expansion of Sureño gang territories has allowed the cartel to expand its influence into Northern California, the report says.
“This ever-increasing zone of influence has caused friction with existing regional gangs that had previously controlled trafficking routes, resulting in threats of violence, homicides, kidnappings, and extortion,” it reads.
San Luis Obispo County has had a documented Sinaloa presence since 2012, the report says.