"Speaking is difficult, but I need to say something important," Giffords said haltingly from a Senate Judiciary Committee witness chair at Congress' first gun control hearing since 20 elementary school children were shot to death in Newtown, Conn., in December.
"Be bold, be courageous, Americans are counting on you," she said.
Giffords was not on the publicly released list of witnesses for the hearing. She and her former astronaut and retired Navy Capt. Mark Kelly were greeted warmly outside the hearing room when they arrived. Giffords was wounded in an assassination attempt in Tucson, Ariz., a little more than two years ago, and has since become a public advocate for gun control.
Kelly also testified, saying both he and his wife are gun owners who support the right to own guns. But he says Congress must strengthen laws to prevent criminals and the mentally ill from getting guns. The two have formed a political action committee called Americans for Responsible Solutions to back lawmakers who support tighter gun restrictions.
In the wake of the Newtown massacre, President Barack Obama proposed a package that includes banning assault weapons, requiring background checks on all firearms purchases and limiting ammunition magazines to 10 rounds.
In testimony prepared for the hearing but released Tuesday, Wayne LaPierre, NRA's executive vice president, said such steps had failed in the past. He instead voiced support for better enforcement of existing laws, beefing up school security and strengthening the government's ability to keep guns from mentally unstable people.
California Sen. Dianne Feinstein, a Democrat and member of the committee, has introduced a bill to ban numerous assault-style weapons as well as high-capacity ammunition magazines.
However, the prospects for passage in the Senate are not strong, in part because of opposition from the NRA and in part from a reluctance among rural-state Democrats to support limitations on firearms.
The Associated Press contributed to this report.