Did cellphones help de-escalate the gang turf wars that tore up cities in the 1980s? A new theory suggests that the arrival of mobile phones made holding territory less important, which reduced intergang conflict and lowered profits from drug sales. Lena Edlund, a Columbia University economist, and Cecilia Machado of the Getulio Vargas Foundation lay out the data in a National Bureau of Economic Research working paper, reports The Atlantic. They estimate that the diffusion of phones could explain 19 to 29 percent of the decline in homicides from 1990 to 2000. “The cellphones changed how drugs were dealt,” Edlund says. In the 1980s, turf-based drug sales generated violence as gangs attacked and defended territory, and also allowed those who controlled the block to keep profits high.
The cellphone broke the link between turf and selling drugs, the paper contends. “It’s not that people don’t sell or do drugs anymore,” Edlund tells The Atlantic, “but the relationship between that and violence is different.” Edlund and Machado used Federal Communications Commission data on cellular-infrastructure deployment and matched it against the FBI’s homicide data. They demonstrated a negative relationship that was even stronger for black and Latino populations. The title of their paper suggests that a crucial aspect of understanding declining crime has been hiding in plain sight for years: “It’s the Phone, Stupid: Mobiles and Murder.” Edlund and Machado are not the first to suggest that phones could have played a role in the decline. Criminologists Erin Orrick and Alex Piquero found that property crime fell as cellphone-ownership rates climbed. Cellphones are far from the only possible explanation. Any measurement that was going up in the 1990s correlates with the decline of violence.