WASHINGTON -- Recent mass shootings like the massacre of first-graders and staffers at a Connecticut elementary school and the increasing deadliness of assault weapons makes a ban on those firearms more urgent than ever, the Senate author of a proposal to prohibit them said Wednesday.
Sen. Dianne Feinstein, a California Republican, made the remark as the Senate Judiciary Committee held a hearing on her proposal, which would also bar ammunition magazines that can hold more than 10 rounds.
But the bruising, difficult path through Congress that the proposal will have was illustrated when the Judiciary panel's top Republican challenged the need for the assault weapons ban. Sen. Charles Grassley, an Iowa Republican, questioned the ban's constitutionality and said it would take the weapons away from people who use them for self-defense.
The hearing was the Senate's third since the Dec. 14 attack on Sandy Hook Elementary School in Newtown, Conn., that killed 20 students and six workers. The Judiciary panel could begin writing legislation as early as Thursday, but that session is likely to be delayed until next week.
Numerous relatives and neighbors of victims of Newtown, as well as other shootings at Aurora, Colo., and Virginia Tech filled the large hearing room.
At one point, Feinstein played a video showing how a bump fire slide, a piece of equipment added to an assault weapon, allows it to rapidly fire many rounds of ammunition, much as a machine gun would.
"The need for a federal ban has never been greater," Feinstein said.
Grassley expressed sympathy for gun violence victims, but said existing gun laws are not being adequately enforced, including background checks designed to prevent criminals from getting weapons.
"We should be skeptical about giving the Justice Department more laws to enforce" when it's not enforcing current ones, Grassley said.
Grassley said he believed Congress will eventually take action on boosting penalties for illegally trafficking guns, on more adequately keeping guns from people with mental problems, and encouraging states do a better job of reporting mental health records of potential gun buyers to the federal background check system.