Perhaps the single most important dereliction of duty by Congress in recent years is the expiration of the ban on assault weapons and large-capacity magazines, which was enacted in 1994 and lasted only for 10 years.

There were signs during the ban that it was beginning to take these especially lethal weapons out of criminal inventories. Gun violence experts believe that trend would have continued, had the ban remained in effect. Instead, Congress allowed it to lapse in 2004. The consequence has been increased use of these weapons in crimes of all sorts ever since.

You can have a lot of additional high-volume gunfire incidents that don’t result in mass shootings...but that’s still a public policy concern. Christopher Koper, George Mason University

A study by Christopher S. Koper and colleagues at George Mason University, recently published in the Journal of Urban Health, points to an especially alarming aspect of this trend. The weapons are showing up more often not only in mass shootings such as the Las Vegas massacre, but in ordinary crimes of violence and attacks on police officers.


“There’s a tendency to focus on mass shootings,” Koper told me. “I’ve tried to draw attention to some of the broader issues beyond mass shootings and at the use of these guns and magazines in crime generally. You can have a lot of additional high-volume gunfire incidents that don’t result in mass shootings — you might have incidents where more than 10 shots are fired but maybe have only one or two victims who are actually shot. But that’s still a public policy concern.”

Mass shootings such as the Las Vegas event account for a very small proportion of total U.S. gunfire violence, but tend to seize the public’s attention because of the sheer number of victims and the sense that they’re random victims, injured just from being in the wrong place at the wrong time, rather than inviting violence through an association, say, with drug dealers or organized crime. Assault weapons magnify the toll because of their murderous efficiency — they allow many more shots to be fired than conventional weapons, which translates into more people getting hit and more of them suffering multiple injuries.

Koper’s research has found that the use of assault weapons in crime declined materially in communities that kept records of guns recovered by police during crime investigations, a decent proxy for the nature of weaponry used in crimes. The decline in recovered assault weapons after the federal ban in 1994, compared to the pre-ban period, ranged from 17% in Milwaukee to 72% in Boston.

But the trend has reversed in many communities. The recovery of assault weapons with large-capacity magazines — the feature that best defines those weapons — has risen by almost 50% in Baltimore, where their prevalence was estimated at 11.1% of gunfire crimes in the first years after the ban expired and 16.5% by mid-2014. In Richmond, Va., their prevalence among seized firearms has more than doubled.


Weapons with large-capacity magazines, which are defined as those that can hold more than 10 rounds at a time, appear to be especially prevalent among guns used in murders of police — assault weapons accounted for up to about 16% of the weapons in those crimes, but large-capacity magazines were seen in more than 40% of those incidents. The 1994 assault weapons ban was enacted following a series of horrific mass shootings, including the 1989 Stockton schoolyard shooting in which five children were killed and 34 children and a teacher were wounded; and a 1991 restaurant shooting in Texas in which 23 people were killed and 27 wounded.

Introduced by Sen. Dianne Feinstein (D-Calif.) and opposed by the National Rifle Assn., the ban was designed to be reexamined after 10 years, but Congress simply let it lapse in 2004 without much examination at all. What was evident almost from the inception was that the ban’s effectiveness was limited by its gaping loopholes. As Koper observed in a book chapter published in 2013, the ban didn’t apply to all semi-automatic weapons, but only those with “features that appear to be useful in military and criminal applications but unnecessary in shooting sports or self-defense.” These included pistol grips on rifles, flash hiders and threaded barrels for silencers.

The most important provision was the ban on large-capacity magazines. That’s because these magazines are “the most functionally important feature” of assault weapons, Koper wrote. Moreover, many semi-automatics that were still permitted during the weapons ban could be fitted with the large-capacity magazines, which now were illegal.

A large percentage of weapons and magazines used by mass shooters would be outlawed by a weapons ban considered, and rejected, by Congress in 2013, according to this survey. (Mother Jones )


Another loophole was the grandfathering of weapons and magazines manufactured before the ban’s enactment date, Sept. 13, 1994. Ownership and transfer of an estimated 1.5 million assault guns and as many as 25 million magazines were thus allowed to continue. Another 4.8 million pre-ban magazines were imported during the ban.

“The ban had mixed effect in reducing crimes with the banned weaponry,” Koper reported in 2013, “because of various exemptions and loopholes in the legislation.” But he said that emerging evidence hinted that it might have worked better had it remained in place for more than its 10 years.

Unaccountably, the string of even more horrific mass slaughters of recent years — the murder of 20 6- and 7-year-olds in Newtown, Conn.; the 2007 fusillade at Virginia Tech that killed 32 and wounded 17; the killing of 14 San Bernardino Christmas party guests in 2015; and many more — hasn’t done much to move the needle on reinstating the assault-weapon ban. Under the circumstances, talk of banning “bump stocks,” an attachment that apparently allowed Las Vegas shooter Stephen Paddock to increase the rate of gunfire from his weapons, looks like a facile sop to gun-control advocates accepted by 2nd Amendment fanatics chiefly to stave off more serious and effective regulations.

The NRA is still fighting other regulations. A 2016 California ballot initiative that required owners of large-capacity magazines to turn them in by the end of June has been blocked by a federal judge presiding over a lawsuit filed by the NRA.


Koper acknowledges that reinstating the ban might not reduce the overall number of gun crimes, in part because some perpetrators would simply move to other weapons. But that doesn’t mean it would be ineffective. “By forcing offenders to substitute other weapons, you’re essentially forcing them to use weapons that are less deadly,” he says. His paper mentions the need for more research on the effects of assault-weapons usage and the impact of regulations. That’s a common complaint of gun violence researchers, who have labored under federal funding limitations imposed at the behest of the NRA.

Koper is wary of drawing any specific conclusions about the assault-weapons ban from the Las Vegas shooting — “It’s hard to look at any one incident and say it definitely would have been prevented,” he says. “But the evidence suggests that when offenders are using these types of guns and magazines in gun crimes and mass shootings they are able to wound and kill more people. In part, the victim tallies are going to be linked to the lethality of the weaponry they have. In general, you’d expect that if less lethal weapons were available, you could perhaps reduce the severity of some of the mass shooting incidents.”

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