PHOENIX — A Senate panel agreed Monday that any Arizona adult should be able to carry a concealed weapon without special training or background check.

The 4-3 vote would create a major loophole in the existing laws that require those who want to have a hidden weapon to undergo special training. This includes classes on when people can legally use deadly force as well as marksmanship.

And it also requires a background check to weed out felons.

The measure alarmed the Arizona Association of Chiefs of Police which sent its lobbyist, John Thomas, to the Senate Judiciary Committee to try to kill the measure.

“SB 1102, if enacted into law, will take Arizona back to the Wild West carry (laws), with no consideration of officer safety,’’ he said.

But Sen. Russell Pearce, R-Mesa, said the change is not as outrageous as it might sound.

He pointed out that all adults have always been able to carry sidearms in Arizona as long as they are visible. All this does, Pearce said, is expand that right to those who might not feel comfortable walking around in public with a gun strapped to a hip.

And Pearce said he thinks it would be good for Arizona if more people were armed.

“There’s not a greater thing you can have out there than a citizen who is armed,’’ he said, calling them “the good guys.’’ He said if there were more people carrying guns “you might have been able to avoid the massacre at Virginia Tech,’’ where a gunman three years ago killed 32 students before turning the weapon on himself.

“I’ve never been afraid of a good citizen being armed,’’ Pearce said. “In fact, our Founding Fathers expected it and demanded it.’’

Thomas said the police chiefs are not concerned about the “good guys.’’

“You’re going to encourage people that are not necessarily good citizens that they could break the law,’’ he said.

“Right now, we do believe that (the requirement for a permit) does stop people from carrying,’’ Thomas said. “They know that if they’re busted with a concealed (weapon) under the current law that they face criminal action.’’

He acknowledged that two other states — Alaska and Vermont — both allow any adult to carry a concealed weapon. But Thomas said the Alaska law has some built-in safeguards for police, like a requirement that anyone who has a gun must inform an approaching police officer that he or she is armed.

Pearce, however, said putting such a requirement into Arizona law would become just another trap for law-abiding citizens to get arrested.

Even if SB 1102 does become law, it will still be possible for Arizonans to get a state-issued permit. Dave Kopp, president of the Arizona Citizens Defense League, said there are several benefits to having one.

For example, a year-old law which allows people to carry weapons into establishments where alcoholic beverages are served applies only to those who have one of those permits. Anyone carrying concealed under this new proposal would have to leave the gun in the car.

Someone with a state-issued permit also can carry their guns into other states which have reciprocity provisions with Arizona, where their residents with similar permits can carry them concealed while visiting Arizona.

Before approving the bill, committee members rejected a proposed amendment by Sen. Ken Cheuvront, D-Phoenix, who sought to tighten up on the sale of weapons at gun shows.

Federal law requires licensed weapons dealers to get proof of citizenship before selling someone a gun. But those laws do not cover gun shows where collectors can buy and sell weapons without the normal checks.

Cheuvront said he believes gun shows are a popular source of weapons for criminals who want to bring them into Mexico. He said requiring proof of citizenship from buyers at these shows would curtail that problem.

But Pearce called the claims that gun-show weapons are winding up in Mexico “a myth put out by the federal administration.’’