So much has been written about the tragic shootings in Arizona that we are reluctant to add to the paper flow. The terrible event has given people the opportunity to express their views on hatred (a word which is variously defined), guns (including Glocks with extra ammunition clips), the right (near, far, and in between) and mental illness (schizophrenia, paranoia, et al.).

We believe that the murders in Tucson were more than 90% the consequence of the shooter’s insanity, and less than 10% due to the political climate. We know he was crazy, but he did fix on this Congresswoman as the object of his twisted rage. We cannot measure the precise components of his delusions, but those who say the crime was primarily the result of Arizona’s loose gun laws and political climate are less accurate, in our judgment, than those who attribute it mainly to the shooter’s schizophrenia. It is remotely possible that his insanity will excuse him from criminal liability, and spare him from execution or a prison sentence, but that is highly unlikely considering the celebrity and status of his victims.

With regard to guns, it seems ridiculous that anyone, crazy or not, can go into a store and buy extra ammunition clips, but remember that all the killing was done with the first clip he used. The clip he bought was said to be illegal from 1994 to 2004, but that law sunset and was not renewed due to the gun lobby. The National Rifle Association has enormous influence in Washington, based in part because it has so many members who feel the way they do and vote that way.

The same Founding Fathers who gave us the First, Fourth and Fifth Amendments in the Bill of Rights gave us the Second Amendment, and it is hard to conclude from the text that it refers only to organized militias. Perhaps it should, but that is not the way it reads. This is the full text:

“A well regulated Militia, being necessary to the security of a free State, the right of the People to keep and bear arms, shall not be infringed.”

We believe that the right to bear arms should be subject to reasonable regulation, and we prefer the New York standard to the Arizona standard, which reflects the views of owners of widely separated homes, some near the border with Mexico, and all a few generations from the Wild West. We approve of what more than 500 American mayors are doing to promote arms control, and respect but regret the fact that tens of millions of Americas feel differently, based on their culture, their attitude, and their perception of danger.

The most important lesson we draw from the Tucson tragedy is relatively simple: There are hundreds of thousands, possibly millions, of mentally ill people in this country who are not institutionalized and not taking proper medication. Occasionally, these people do terrible things.

The first mass killer, and possibly the role model for the others, was Charles Whitman, who killed 16 people, shooting from a tower at the University of Texas in Austin on August 1, 1966. He was shot by the police.

The Virginia Tech murder of 32 students and faculty in April 2007, less than four years ago, was the most deadly instance of this kind. The killer was 23 years old and committed suicide after the shootings.

The slaughter which caused the most intense reaction took place at Columbine High School on April 20 (Hitler’s birthday), 1999, where two high school seniors murdered death twelve other students and one teacher before shooting themselves.

Other similar episodes have received lesser attention, but the issue of mental health is a factor in all these killings. The question arises: What do you do with people who are reasonably believed to be mentally ill, but have not yet done any harm to themselves or others? Can they, or should they, be locked up because they present risk factors? Who measures the risk, and what are the standards for any determination?

If we believe that nothing can be done until the ill person acts out his fantasies, we may be condemning innocent strangers or bystanders to death. Should we call those murders the price of living in a free society? These are the questions that should receive the most attention after the tragedy in Arizona. If we are able to find answers, we may save the lives of other people: Members of Congress, judges, children, ordinary Americans who may be doomed by society’s refusal to respond to strong clues that some people are mentally ill.

We are even uncomfortable with words like “crazy” and “wacko” because they are politically incorrect. Politicians today risk their careers by using words that the language police consider inappropriate under the latest and most refined standards. Elegant language, however, is not the major difficulty in dealing with mental health issues. We believe there are no ready answers, but certainly there are things that can be done that are not being done today.

Are there any standards of conduct that should be applied to non-criminal behavior where the person involved might, or might not, endanger others? Can people be deprived of their liberty because of a mental defect or tendency that either is, or is not, treatable? Who, if anyone, has an obligation to report behavior which indicates mental illness? To what authorities should concerned citizens address their observations of the subject’s words, threats or actions? Would they be subject to lawsuits by a person whose conduct they felt was potentially dangerous?

You can see why the policy in this area is often to do nothing. Perhaps, with insight, we can do something to protect our citizens from the tragedy we have so recently endured, and from others that are likely to occur in the years ahead.

Mr. Stern, president of New York Civic, is a frequent contributor to The New York Sun.