Editor's note: Steve Kozachik is vice mayor and a member of the Tucson City Council.
(CNN) -- In defiance of Newton's law that every action has an equal and opposite reaction, any discussion of legitimate controls on the use, handling and sale of firearms routinely yields an explosive overreaction of opposition. I learned that firsthand when I organized a voluntary gun buyback program for January 8 in Tucson, Arizona.
It was the tipping point for me to change my party affiliation from Republican to Democratic.
On January 8 in 2011, a seriously deranged young man murdered six people, including a 9-year-old girl, and wounded 13, including Rep. Gabby Giffords, during a 45-second shooting rampage in Tucson. He was finally subdued when he stopped to change clips in his semiautomatic weapon, after firing 31 rounds.
In the immediate aftermath, our community came together as one in our grieving over the deaths and in our resolve to do what we could to prevent a repeat of the tragedy.
But the irrational fears of the gun lobby succeeded in shouting down the debate, and in the intervening two years not a single piece of meaningful legislation has been adopted that would even begin to solve the problem.
I was the target of some of that violent overreaction in the two weeks leading up to the buyback. Thinly veiled threats were leveled at me. I was referred to as "Hitler." The response made it clear the event I was planning hit a nerve among a group who evidently believe the proper disposal of a firearm is tantamount to the desecration of a holy icon.
Guns are not fetish objects. The buyback was simply an offer to people who were uncomfortable with having a weapon in their homes to trade those weapons into the Tucson Police Department in exchange for a $50 grocery gift card. More than $10,000 in gift cards were distributed during the event.
The money I used to buy those cards was donated in just under two weeks by Tucson residents, who still cling to the hope we will re-engage on the topic of rational gun control. They showed that the loud voices are not going to shout down the discussion this time around.
But on the periphery of my buyback, and on the periphery of rational discourse, was a group of gun and NRA enthusiasts holding a "cash for guns" firearms flea market. They held it on the boundary of the police department parking lot in which my buyback was taking place.
In Arizona, it is legal for a person to walk up to another on a street corner, hand him cash for a firearm and simply walk off with it, with no need for a background check into his psychological or criminal history. That was exactly what happened with those who came to my buyback to "score some deals" on weapons by outbidding the gift cards I was offering.
I was a Republican at the time, but less than one week after the buyback, I chose to switch parties. I believe there is a centrist element among the rank and file in the GOP, but the leadership is led by the far right and openly beholden to the NRA and the gun lobby. It is that rigid ideology that is driving the party into irrelevancy. The overreaction to the gun buyback made it clear that, in Tucson at least, the Republican Party is out of touch with the values of the community.
The cash for guns event clearly highlighted that anyone, a criminal or someone who is mentally ill, can immediately buy a gun with no questions asked in Tucson. It's obvious that public safety demands that background checks be incorporated somehow in private, person-to-person purchases of guns.
That really is low-hanging fruit in the regulation of weapons sales. Legislators have got to stand up to the gun lobbyists who resist even this minimal change in the law and adopt it -- federally and immediately.
Consider if the Tucson shooter had needed to change clips after just five rounds had been fired, or even 10. The carnage of the day would have been significantly decreased. Lives would have been saved. The size of gun magazines is also low-hanging fruit in this conversation.
So is the need to stop selling armor-piercing ammunition on the open market. Unless the goal is to kill a police officer, certainly rational people can agree that restrictions on the manufacture and sale of this sort of ammunition is in order.
Over the past three years, the Arizona Legislature, with a Republican supermajority, has adopted statutes that have been offensive to Latinos, women and youth. I have openly resisted those bills, and after the recent elections in which those three demographic groups rejected the Republican brand, I had hoped things would change, and that the party leadership would resist the continuing lurch to the far right.
But even after 20 schoolchildren were killed in Newtown, leaders of the GOP have shown no inclination to resist the gun lobbyists who fund campaigns, but who come empty-handed when asked to craft reasonable gun legislation.
Until the Republican Party hemorrhages more and more centrists, leaders will not wake up to the damage they're doing to themselves and the party. The debate over rational gun control legislation is an opportunity for them to engage in a productive manner to make this nation safer.
Follow us on Twitter @CNNOpinion
Join us on Facebook/CNNOpinion
The opinions in this commentary are solely those of Steve Kozachik.