IOWA SEN. CHARLES GRASSLEY, the top Republican on the committee: "The 1994 assault weapon ban did not stop Columbine. The Justice Department found the ban ineffective."
THE FACTS: The 2004 study conducted for the Justice Department did not conclude the decade-old ban was a failure or a success. The nuanced report found that the effects of the ban "have yet to be fully realized" and it might take years to see results directly attributable to the prohibition on certain weapons and large capacity magazines. The ban expired later in 2004.
The study's author, Christopher S. Koper, then of the University of Pennsylvania, considered the restrictions modest and speculated that they would have similarly measured results — perhaps as much as a 5 percent decline in gunshot victimization over time if the ban were kept in effect.
His main finding: There were not enough statistics and time to understand the impact of the ban
and "it may take many years for the effects of modest, incremental policy changes to be fully felt, a reality that both researchers and policy makers should heed."
The study made no recommendation whether the ban should be renewed. But it said that if the ban expired, it was "possible, and perhaps probable" that new assault weapons and large capacity magazines coming into the market "will eventually be used to commit mass murder."