Lawmakers are weighing the benefit of accessibility with the necessity of security in the aftermath of a shooting at a political meet-and-greet outside an Arizona supermarket.

Democratic Rep. Gabrielle Giffords remained in critical condition Sunday after being shot in the head at the event Saturday. The gunman killed six people, including a federal judge and a 9-year-old girl, and wounded 14 others, authorities said. The suspected shooter is in custody.

There was no security at the political gathering, Pima County Sheriff Clarence Dupnik said. At such events, "there's never security unless there's advance intelligence that there may be a problem of some kind," he said, noting that Giffords often attends as many as eight events in a single day.

"But it's not unusual for all public officials to get threats constantly, myself included. And that's the sad thing about what's going on in America. Pretty soon, we're not going to be able to find reasonable, decent people who are willing to subject themselves to serve in public office," Dupnik said.