In the wake of Saturday's shooting of Representative Giffords and 19 others outside a Tucson, Ariz., supermarket, the local police chief linked the attack to vitriolic political rhetoric. Others, however, see the event as the misguided action of a disturbed individual and nothing more.

Saturday's attack has heightened the alert level of members of Congress, but many are resisting increased police presence when visiting with constituents, as Giffords was at the time of the attack.

Democratic whip Steny Hoyer of Maryland said Saturday's shooting struck at the heart of American politics. “This is not simply an attack on Ms. Giffords. This is an attack on democracy itself, on the ability ... to peaceably assemble, to come together to talk to one another,” he said on CBS’s "Face the Nation."