There's no evidence so far that Jared Lee Loughner, the 22-year-old college dropout accused of shooting Rep. Gabrielle Giffords and killing six others in Arizona, has a political agenda or belongs to any particular political group. But his attempted assassination of a member of Congress who had endured death threats and attacks on her office over votes she cast in Washington sparked intense hand-wringing over whether the highly partisan political rhetoric so common today may have played a role -- followed by passionate finger-pointing over exactly what provoked this man to kill.

Republican House leaders have already canceled their scheduled business for next week, including a vote to repeal President Obama's health care reforms scheduled for Wednesday. Giffords' office had been vandalized and she had received death threats after having supported those reforms.

"Republicans are clearly responding as if they feel somewhat incriminated," said University of Michigan political science professor Lisa Disch. "On the one hand, they are acting very quickly to distance themselves from the incident, but on the other hand, they seem to be feeling as if they have been caught at something; caught at using rhetoric that is incendiary."

Tea Party groups have combed through their list of members to ensure Loughner is not among their members, but that has done little to assuage liberal groups, some media outlets, and even law enforcement officials from tying Saturday's shooting to the conservative political movement that propelled Republicans to historic victories in last year's congressional elections.

During those campaigns, Giffords' district was depicted on the Web site of former Republican vice presidential nominee and Tea Party champion Sarah Palin with the cross hairs of a rifle scope superimposed on it. The image has been taken down from Palin's Web site, but that didn't stop Markos Moulitsas, founder and publisher of the liberal blog Daily Kos, from tweeting on Saturday, "Mission accomplished, Sarah Palin."

Pima County Sheriff Clarence Dupnik, a Democrat who has openly criticized the Tea Party, blamed the shooting on "vitriolic rhetoric" of political groups and transmitted by media outlets.

"When the rhetoric is about hatred, about mistrust of government, about paranoia about how the government operates to try to inflame the public on a daily basis, 24 hours a day," Dupnik said, "it has an impact on people, especially people who have unbalanced personalities to begin with."

Senate Majority Whip Richard Durbin, D-Ill., said Sunday on CNN's "State of the Union" that the Tea Party needs to dial back the rhetoric, citing Palin's May 23, 2010, tweet: "Commonsense Conservatives & lovers of America: Don't Retreat, Instead -- RELOAD!"

"These sorts of things," Durbin said, "I think invite the kind of toxic rhetoric that can lead unstable people to believe this is an acceptable response."

There is no evidence Loughner took action in response to anything said or published by the Tea Party or any other group. If anything, his political views appear muddled and some have described him as "goth" and "left wing."

"You know, his favorite books are the 'Communist Manifesto' and 'Mein Kampf,' " Rep. Cathy McMorris Rodgers, R-Wash., said on "Fox News Sunday". "I think it's important that we recognize that this is an individual that has mental challenges, and we need to act appropriately in dealing with him and making sure that justice prevails here."