The increased use of cellphones reduced US homicide rates in the 1990s, according to new research distributed by the National Bureau of Economic Research.
The popularity of cellphones undermined the turf-based business model for illegal drug dealing, a co-author of the study suggests. That, in turn, may have undercut street gangs’ drug profits.
The researchers found the link between mainstreamed cellphone service and the reduction in 1990s homicide rates after analyzing data from 1970 to 2009. Homicides declined by about 10,000 between 1990 and 2000, they found.
The study, entitled “It’s the Phone, Stupid: Mobiles and Murder,” estimated that roughly 1,900 to 2,900 of that decrease could be explained by the mainstreaming of cellphones.
Cellphones may have been behind the decline in violent crime in the 1990s by reducing drug-related deaths, said co-author Lena Edlund, an associate professor of economics at Columbia University. “When users had cellphones, they didn’t have to buy on the corner,” Edlund told MarketWatch. “The street market for drugs became less important.”
Edlund and co-author Cecilia Machado, an assistant professor at the Getulio Vargas Foundation in Rio de Janeiro, propose that the cellphone effectively cut out the middleman. Phones also allowed parties to handle payment and delivery separately, they said, potentially reducing the likelihood of an altercation.
“A move away from turf-based dealing may have reduced the ability to cartelize drug sales, dented profits and dulled the allure of gang life,” the authors added.
Edlund and Machado examined county-level mortality data from the vital statistics system and mortality data from the Federal Bureau of Investigation’s supplementary homicide reports (SHR), using the density of antenna structures (like towers) as a proxy for cellphone service expansion.
The researchers found stronger effects among male black or Hispanic victims. They also saw stronger effects for homicide categories more closely linked with drugs and gangs (“Narcotics-gang,” “Argument” and “Theft”) and observed concentrated effects in urban counties, where turf wars tend to play out. And there was no effect on “wife killings,” they wrote, “consistent with gang members or drug dealers not being the marrying kind.”
As for more recent year-over-year increases in violent crime — the US murder rate increased in 2015 and 2016, for example — Edlund and Machado pointed out that homicide rates had remained relatively low, suggesting a “fundamental regime shift” overall.
“This research suggests that no, they’re not going back up again,” Edlund said. “The market for drugs has changed and we’re not going back to the street business model.”