Authorities in Texas had warned weeks ago that tensions were escalating between rival motorcycle gangs.
On Sunday, the rest of the country learned about it too when a shootout erupted among the gangs at the Twin Peaks in Waco, Texas, killing nine people and injuring another 18.
About 170 bikers were arrested. In some parts of the country, state and federal law enforcement consider these biker gangs a significant threat.
Here & Now's Robin Young delves into the history and subculture of outlaw motorcycle gangs with James Quinn, a professor at the University of North Texas, who studied gang culture.
- James Quinn, a professor at the University of North Texas.
This segment aired on May 19, 2015.