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Tuesday, February 26, 2013

The effectiveness of background checks for gun sales

There’s been some debate lately about what to do about gun violence in the United States. A vast majority of citizens on the left and the right are in favor of universal background checks (asking about prior felonies and mental illness) for all gun purchasers. But would such a measure be effective? According to a new study by Garen Wintemute of the University of California, Davis, it would be.

Wintemute based his analysis on currently existing laws and conditions. To begin with, he differentiates between licensed dealers and private sellers. The former must collect information from their customers before selling them weapons and then keep permanent records on each sale. Private sellers have no such federal requirement, although some states do require background checks for private party sales. There is no limit as to how many guns a person can sell before being legally considered a dealer rather than a private seller.

In many estimates, 40% of gun sales do not involve licensed dealers and thus may not involve background checks. That number increases to over 90% for ‘prohibited’ people who would not pass a background check (presumably the sort of people we’d prefer to keep guns away from) and to virtually 100% for juveniles seeking to buy weapons.

Wintemute then compared gun sales in California, where even private sellers must do background checks on their customers, and four states with no such restrictions (Arizona, Nevada, Texas and Florida). In California gun shows, even private party sales are conducted through licensed transfer agents. Sales in the other states can be, and usually are, directly between seller and buyer. There were two consequences of this. First, the gun shows across the California border in Nevada were full of California buyers (over 30% by license plate count). Second, there were six times as many illegal gun purchases (buying a gun for someone else who could not pass a background check) in the neighboring states as in California.

These data strongly suggest that federally mandated universal background checks and record keeping would prevent many questionable people from purchasing firearms. People who could not pass a check in California would not have the option of going to Nevada to get their weaponry. This would be particularly helpful in cities like Chicago, which have strict gun regulations but which get a huge influx of weapons from just outside the city limits.

No one is suggesting that universal background checks would solve all our problems. They would however, undoubtedly reduce the number of guns available to people who should not be trusted with guns, especially people with violent or unstable histories. It’s no wonder that over 90% of Americans now favor enacting laws requiring such measures.

For more details, watch Wintemute explain his findings below.

Update 4/2013: Mayors Against Illegal Guns has a fact sheet on background checks.