Suicide, Homicide and Guns

There are a number of reasons social psychologists are confident that the availability of firearms is a major cause of violent death. In an earlier post, I discussed some of the many studies of the priming effect of weapons on aggression. These studies suggest that the presence of weapons, or pictures of weapons, increases aggressive thoughts and behaviors. Since these are laboratory experiments in which participants are randomly assigned to conditions, they permit a relatively strong inference of causality. However, due to the obvious constraints on our willingness to provoke aggression in the lab, some people find these studies to be artificial, and feel more comfortable with field studies of the availability of firearms in the real world.

Many of these field studies are ecological, in the sense that they measure both the availability of weapons and the number of deaths at the aggregate or population level. For example, in an early study, Archer and Gartner (1987) found that the homicide rate in countries around the world is highly correlated with the availability of handguns. But correlation does not mean causation, and the countries involved in this comparison differed in many other ways besides their weapons policy. Most recent studies have attempted to statistically control for alternative explanations such as urbanization, poverty, alcohol use, depression, etc. However, since the number of alternative explanations is theoretically infinite, there are limits to this approach.

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Gun advocates also attack the validity of the measures used in these studies. For example, in most studies, the availability of firearms is determined from gun registration statistics. However, it could be argued that many homicides are the result of unregistered guns in the hands of criminals. Can this assumption account for the positive correlation between gun availaility and murder? Yes, but only if you assume that those areas that contain the most legally registered guns also contain the most illegal ones.

A more time-consuming but more conservative procedure is to start with a suicide or homicide and work backward, looking at each individual case. In these observational studies, for each suicide or homicide victim, regardless of the manner of death, it is determined whether firearms were available in the home. These people are compared to a matched control group of people who did not commit suicide or were not murdered, such as participants in a national health survey. This allows you to compute a likelihood ratio—the likelihood of a homicide or suicide when a gun is available compared to the likelihood when it is not.

In a study published this week, Andrew Anglemyer of the University of California at San Francisco and his colleagues did a thorough literature search and located 15 such observational studies. They then did a meta-analysis of these data. A meta-analysis is an analysis of analyses, a way of statistically combining the results of several studies to estimate the size of an effect. These were their findings:

• You are 3.24 times more likely to commit suicide when a firearm is readily available than when it is not. These findings do not differ for men and women.

• You are 1.94 times more likely to die of a homicide with a gun in the home than without. This effect differs for male and female homicide victims. Women are 2.94 times more likely to be killed when a firearm is available, while for men, the effect is almost nil—only 1.29 times more likely.

The meta-analysis shows that having a firearm available has a greater influence on suicides than on homicides. This makes sense, because most firearm suicides kill themselves with their own gun, while most firearm homicide victims are killed with someone else's gun.

The homicide data show that firearm availability only increases the risk for female victims. Other studies show that women are most likely to be murdered by someone they know. This suggests that firearm availability makes it easier for domestic violence to become lethal. On the other hand, there is no evidence that owning a firearm increases the risk of homicide for men, since they are usually not killed with a gun belonging to themselves or a family member.

In an accompanying editorial, David Hemenway, a leading authority on firearm victimization, points out that this pattern of results is due to Anglemyer's choice to analyze only individual-level, observational studies. He argues that the meta-analysis substantially underestimates the effects of firearm availability on male homicides because it only asks whether the victim had access to a gun, when the more important question is whether the perpetrator had access to a gun. Therefore, he suggests that future studies of homicides be either population-level ecological studies which measure the number of guns in the community, or individual-level observational studies of the availability of firearms to perpetrators rather than victims.

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Symbolic Racism and Gun Ownership

Open Carry

Breathing While Black

Symbolic Racism and Gun Ownership

In the past, I've mentioned the fact that a correlation between two variables does not necessarily mean that one causes the other. I'm usually reluctant to report correlational findings in this blog. However, since some variables are difficult or impossible to manipulate experimentally, simply disregarding correlational research is not an option. The question then becomes: How well does this particular correlational study control for alternative explanations? I think this one is worthy of our consideration.

I've also previously explained the difference between old-fashioned racism and modern or symbolic racism. Old-fashioned racism refers to the endorsement of statements that are obviously and blatantly racist, such as the belief that blacks are genetically less intelligent than whites, or that black and white people should be segregated. Because it is not socially acceptable to express these attitudes, whites typically score low in old-fashioned racism and it usually does not predict behavior very well--although it does predict membership in the Republican party.

Modern or symbolic racism (sometimes also called racial resentment) refers to prejudice that is revealed in subtle, indirect ways. In the present study by Kerry O'Brien and her colleagues, symbolic racism was measured using these four items from the Symbolic Racism 2000 Scale:

1. Irish, Italian, Jewish and many other minorities overcame prejudice and worked their way up. Blacks should do the same.
2. Generations of slavery and discrimination have created conditions that make it difficult for blacks to work their way out of the lower class.
3. Over the past few years, blacks have gotten less than they deserve.
4. It's really a matter of people not trying hard enough; if blacks would only try harder, they could be just as well off as whites.

As you can see, it is possible to endorse these items and still believe that you are not a racist. However, symbolic racism predicts policy preferences that whites (sometimes erroneously) think are harmful to blacks, such as opposition to welfare or support for punitive crime policies. These items were scored on a 5-point scale from “strongly agree” to “strongly disagree,” with items 2 and 3 reverse-scored. A participant's symbolic racism was his or her average score on the four items.

The data come from the American National Election Study, a large, representative panel study of Americans conducted in 2008 and 2009. Only participants who identified themselves as white were included. Three gun-related questions were analyzed: having a gun in the home, opposition to a ban on having guns in the home, and support for permits to carry concealed weapons. Of the literally hundreds of questions that were asked in the survey, the following were deemed to be relevant to the research question and were included in the analysis as control variables: gender, age, education, income, region (the South vs. other states), political party, conservatism, and anti-goverment sentiment.

There was a significant relationship between symbolic racism and having a gun in the home, even after statistically eliminating the effects of all the control variables. For each 1-point (out of 5) increase in symbolic racism, there was a 50% increase in the likelihood of owning a gun. Symbolic racism also predicted support for concealed carry, after eliminating the effects of the control variables and gun ownership. In this case, a 1-point increase in symbolic racism was associated with a 28% increase in support for concealed weapon permits. The question measuring opposition to a handgun ban, however, turned out to be highly correlated with gun ownership. If you own a gun, you don't want it taken away. Therefore, if you eliminate the effect of gun ownership, opposition to gun control is not related to symbolic racism.

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What are we to make of the relationship between symbolic racism, on the one hand, and both gun ownership and opposition to gun control, on the other? Correlation does not mean causation. Whenever two variables, A and B, are correlated, there are three possibilities: A causes B, B causes A, or both A and B are jointly caused by a third variable, C. 

It is certainly plausible that being a racist might cause you to buy a gun for protection from black people. The association between symbolic racism and support for more punitive crime policies is consistent with these results.

Although it may be less obvious, I think there's a real possibility that gun ownership is a cause of racism. Most gun owners claims that their weapons are needed for protection. Could gun owners be trying to justify being armed by exaggerating the extent to which they are under threat by blacks, for example?

As noted, it's possible that some unmeasured third variable explains these results. The number of potential third variables is theoretically infinite. However, the authors have covered the variables that are traditionally associated with gun attitudes, and most of these control variables actually are associated with opposition to gun control or owning a gun. Being a male, from a southern state, a Republican, a conservative, and having anti-government views all individually predict opposition to gun control. Having less education means you are more likely to have a gun in the home. But symbolic racism has an effect over and above all these other variables.

Whites have twice the rate of gun ownership as blacks. As the authors note, the irony of these results is that whites seldom use handguns for self-protection, from blacks or anyone else, but are more likely to use them to commit suicide or shoot someone accidentally—usually a friend or family member. While white racists may think they are protecting themselves from hostile black people, they may actually be thinning their own herd.

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Suspicions Confirmed

Old-Fashioned Racism

Appeal to an Unlikely Scenario

I mentioned in a previous post that I am currently taking an online course in critical thinking through Coursera. This week, one of our topics is fallacies of relevance. A fallacy of relevance is an argument in which the premises are of questionable relevance to the conclusion. An example is an appeal to an unlikely scenario.

Yesterday, the Senate Judiciary Committee held a hearing on Senator Dianne Feinstein's (D-CA) proposal to reinstate the ban on assault weapons and to ban high capacity magazines (clips holding more than ten rounds). Most of the media attention went to two celebrities who testified, former Representative Gabrielle Giffords and NRA president Wayne LaPierre. All three witnesses who argued against the bill maintained that assault weapons are needed by law-abiding citizens for self-defense in the event of an attack by armed criminals. However, as Senator Sheldon Whitehead (D-RI) pointed out, none of the anecdotes of successful self-defense involved an assault weapon or high-capacity magazine. They all utilized traditional weapons such as pistols or shotguns, access to which is not threatened by the legislation.

However, the pro-gun lobby's imagination is not constrained by reality, so one of the witnesses, Gayle Trotter of the Independent Women's Forum, entertained the Senators with the following hypothetical scenario:

An assault weapon in the hands of a young woman defending her babies in her home becomes a defense weapon. And the peace of mind that a woman has as she's facing three, four, five violent attackers, intruders in her home, with her children screaming in the background, the peace of mind that she has knowing that she has a scary-looking gun gives her more courage when she's fighting hardened, violent criminals. If we ban these weapons, you are putting women at a great disadvantage . . .

Appeals to unlikely scenarios should be evaluated by assessing the positive or negative consequences put forward in the scenario, weighted by their probability of occurrence—which in an unlikely scenario is low. They are compared to the positive or negative consequences of the alternative course of action, in this case, not banning assault weapons, weighted by their probability of occurrence. The conclusion is obvious.

Unfortunately for Ms. Trotter, she agreed to be interviewed on The Last Word with Lawrence O'Donnell last night. He effectively deconstructed her argument and made her look quite silly.

Another example of the mischief done by appeals to unlikely scenarios is the defense of torture which asks us to imagine that we have captured a terrorist who refuses to tell us the location of a bomb which will kill a large number of people. Given limited time, would we not torture him to find the bomb? One of the reason people find these unlikely scenarios to be plausible is that they are often presented in fictional films and television programs, and we later remember these stories as having been true.