The Texas legislature is on the verge of passing a law permitting concealed weapons on University campuses, including the University of Texas where just this Fall my co-author Marcin Peski was holed up in his office waiting out a student who was roaming campus with an assault rifle.
This post won’t come to any conclusions, but I will try to lay out the arguments as I see them. More guns, less crime requires two assumptions. First, people will carry guns to protect themselves and second, gun-related crime will be reduced as a result.
There are two reasons that crime will be reduced: crime pays off less often, and sometimes it leads to shooting. In a perfect world, a gun-toting victim of a crime simply brandishes his gun and the criminal walks away or is apprehended and nobody gets hurt. In that perfect world the decision to carry a gun is simple. If there is any crime at all you should carry a gun becuase there are no costs and only benefits. And then the decision of criminals is simple too: crime doesn’t pay because everyone is carrying a gun.
(In equilibrium we will have a tiny bit of crime, just enough to make sure everyone still has an incentive to carry their guns.)
But the world is not perfect like that and when a gun-carrying criminal picks on a gun-carrying victim, there is a chance that either of them will be shot. This changes the incentives. Now your decision to carry a gun is a trade-off between the chance of being shot versus the cost of being the victim of a crime. The people who will now choose to carry guns are those for whom the cost of being the victim of a crime outweigh the cost of an increased chance of getting shot.
If there are such people then there will be more guns. These additional guns will reduce crime because criminals don’t want to be shot either. In equilibrium there will be a marginal concealed-weapon carrier. He’s the guy who, given the level of crime, is just indifferent between being a victim of crime and having a chance of being shot. Everyone who is more willing to escape crime and/or more willing to face the risk of being shot will carry a gun. Everyone else will not.
In this equilibrium there are more guns and less crime. On the other hand there is no theoretical reason that this is a better outcome than no guns, more crime. Because this market has externalities: there will be more gun violence. Indeed the key endogenous variable is the probability of a shootout if you carry a gun and/or commit a crime. It must be high enough to deter crime.
And there may not be much effect on crime at all. Whose elasticity with respect to increased probability of being shot is larger, the victim or the criminal? Often the criminal has less to lose. To deter crime the probability of a shooting may have to increase by more than victims are willing to accept and they may choose not to carry guns.
There is also a free-rider problem. I would rather have you carry the gun than me. So deterrence is underprovided.
Finally, you might say that things are different for crimes like mugging versus crimes like random shootings. But really the qualitative effects are the same and the only potential difference is in terms of magnitudes. And it’s not obvious which way it goes. Are random assailants more or less likely to be deterred? As for the victims, on the one hand they have more to gain from carrying a gun when they are potentially faced with a campus shooter, but if they plan make use of their gun they also face a larger chance of getting shot.
NB: nobody shot at the guy at UT in September and the only person he shot was himself.
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February 20, 2011 at 10:50 pm
twicker
Of note, we have several places on this planet where nearly everyone does carry a gun (or only goes into places that are well-lit, well-populated, and well-armed).
I’ll use South Africa as my main example, since it’s absolutely not a failed state by any generally-accepted definition of the term. There, the populace is far better armed than here (go into any major – or minor – shopping mall, and you’ll find a home security store with a nice selection of weapons). The criminals know this. What changes is not the frequency of crime; what changes is that criminals now start the crime by killing the victim (keeps them from shooting back), and then they commit the lesser crime.
The more-recent twist that I’m aware of is in home burglaries: previously, they’d kill any inhabitants, then rob the place. Now, they force the inhabitants to reveal the combination to the safe, and *then* kill them.
Going back to the point of the post:
I’d submit that you’ll achieve a *better* equilibrium if relatively few people have guns – enough people to deter the criminals that might be easily scared off (likely a relatively small proportion of the criminal population, but some), but not so many as to prompt the rest of the criminals to shoot first (since there’s still a high probability of somewhat succeeding in the crime without having someone dead, or at least wounded, at the end of it).
February 20, 2011 at 11:02 pm
A.F Walking
Thanks for a thoughtful consideration of this topic.
You say, in regards to a ‘perfect world’:
“And then the decision of criminals is simple too: crime doesn’t pay because everyone is carrying a gun.
(In equilibrium we will have a tiny bit of crime, just enough to make sure everyone still has an incentive to carry their guns.)”
We know we don’t live in such perfection – but the assessment that criminals will be less likely to commit armed and/or violent crime seems validated by recent statistics (here – https://spreadsheets.google.com/ccc?key=0AonYZs4MzlZbdGhycDRPQlN1dTBoMzJWOTk0Uk9DRVE&hl=en#gid=0), which show that in Vermont in 2009 there were no firearms related murders reported. Vermont has the most relaxed gun carry laws in the Union, where concealed carry requires no ‘permission’ and on that basis it has to be assumed that any or all are concealing a firearm that they know how to use effectively. On the other hand, many of the States and municipalities that have the most violent gun crime also have the most prohibitive gun carry and ownership ordinances (DC for example).
The equilibrium point is interesting too, in that despite the fact there is violent gun related crime – not everyone, who currently could carry, is carrying. I don’t think this is about ‘freeloading’, it’s just some people never will carry. And despite satirical legislation such as this – http://news.yahoo.com/s/usnw/20110202/pl_usnw/DC41625_1, I don’t think any one is seriously proposing that carrying be made a legal requirement. Yet it could work, couldn’t it?
I don’t think the decision to carry results in a trade off of being shot or not. What it provides, is an option to resist and protect if and where appropriate. The ‘decision’ to be shot is not ever the victims, and they may just as readily be shot unarmed and placating and pleading with the perpetrator! An armed citizen has the choice and option to intervene and to defend themselves, but are not required to do so.
Ir certainly seems that during the 66 Whitman episode – http://en.wikipedia.org/wiki/Charles_Whitman, armed civilian intervention assisted in bringing the shooting spree to an end.
In conclusion, I would suggest we all stand to gain increased security when the responsible citizenry is armed.
February 21, 2011 at 12:26 am
twicker
A.F., you’re cherry-picking with Vermont and DC.
Tell ya what: I’ll cherry-pick, too:
Louisiana:
Age of purchasability: 18
Restrictions: pretty much none, except for a permit required for concealed carry (no licensing, no registration — see http://www.criminaldefenselawyer.com/gun-possession-use-laws/louisiana.htm)
2009 Firearms murders per 100,000 population (using your spreadsheet): 10.46
Connecticut:
Age of purchaseability: 21
Restrictions: Registration, license, and permit required for carrying handguns (nothing for rifles/shotguns), permit required for purchasing handguns and assault weapons (source: http://www.criminaldefenselawyer.com/gun-possession-use-laws/Connecticut.htm)
2009 Firearms murders per 100,000 population (using your spreadsheet): 1.99
Now, A.F., your logic was that fewer restrictions = more carrying, which makes sense. Thus, Louisiana, with far, far fewer restrictions and the ability to buy everything at 18 instead of 21, should have far, far more people carrying (which I suspect is true; again, this makes sense). Your logic then suggests that this means that there should be less gun violence — when in fact there are almost 10x as many deaths, by your numbers, in Louisiana than in Connecticut.
Let’s say that a different way: If you live in the ultra-relaxed state of Louisiana, then, in 2009 (which, let’s remember, is only one year out of, oh, decades), you would have been almost 10 times — 10 TIMES more likely to die, or know someone who died, because of a firearm murder than if you lived in the comparatively restrictive state of Connecticut. And that’s even accounting for the fact that statewide statistics allow for a smoothing over of the outsize effects of big city violence (which causes DC’s spike).
Of note, while Vermont has the least-restrictive, California has some of the most-restrictive – by far. Its number (again, by your spreadsheet)? 3.7 firearm murders per 100,000. Or, put another way, you were almost three times as likely (2.83x as likely, to be more precise) to experience a firearm related murder in ultra-lax Louisiana than in uber-restrictive California.
Other states more dangerous (in 2009), and much less restrictive, than either Connecticut or California:
+ Alabama (8.02 firearm murders per 100,000)
+ Georgia (4.78)
+ Mississippi (5.64)
+ North Carolina (4.01)
+ South Carolina (4.63)
+ Tennessee (4.81)
Not seeing the evidence for your proposition. At all.
And I’ll leave you with a final comment about making broad generalizations from one year’s worth of data:
Vermont’s murder/non-negligent homicide rate, 2007: 1.9/100,000 (i.e., 12)
Vermont’s murder/non-negligent homicide rate, 2008: 2.7/100,000 (i.e., 17)
Vermont’s murder/non-negligent homicide rate, 2009: 1.1/100,000 (i.e., 7)
In other words: Vermont’s rates are so incredibly low to start out with, and it has such a small population, that no one single year really tells any story about anything except for that particular year (less of a problem with other states, but it *is* still a problem with other states). You really can’t use a single year to prove or disprove any hypothesis when it comes to a small place like Vermont.
Especially because, as states go, Vermont is a definite outlier. A.F., given that you love Vermont’s gun laws (which come through its overwhelmingly Democratic legislature and its succession of extremely liberal governors), I’m guessing you also love the other things about Vermont that lead to the low overall rates of crime and violence – like the fact that have such a communal ethic that they keep sending a Socialist (Sen. Bernie Sanders) to the US Senate every six years, and the fact that they’re seriously considering abolishing private insurance in favor of a single-payer system (http://www.kaiserhealthnews.org/Stories/2011/February/08/vermont-governor-shumlin-single-payer.aspx)? Because, frankly, these communal values are why Vermont looks more like, well, Vermont, and not like Louisiana. If you want the gun laws with low crime, you need to accept the socialist aspects, too.
Sources:
http://www2.fbi.gov/ucr/cius2007/data/table_05.html
http://www2.fbi.gov/ucr/cius2008/data/table_05.html
http://www2.fbi.gov/ucr/cius2009/data/table_05.html
February 21, 2011 at 10:29 am
dilbert dogbert
Lots of long windedness here. The short story is the criminal picks the time and place of his crime. The victim does not have that choice except not to go where there is more risk. The criminal already has his gun out and the victim still has his in his waistband. I call that for the criminal. The criminal also has the incentive to shoot first as the victim is armed and dangerous.
Just my short 2 cents.
February 21, 2011 at 5:42 pm
karateconomist
I agree with the conclusion that it’s not clear whether crime would be reduced or not, but it’s worth noting that the person who carries has the option not to fight and simply hand over his wallet. The marginal person is not indifferent between being a victim and risking a shootout. He’s indifferent between the costs of carrying and the option value of carrying.
February 21, 2011 at 6:41 pm
Peter T
All the argument about individual incentives to carry/shoot/defend are misplaced. As noted above, the drivers are social.
Any criminologist will tell you that a very large proportion of crime is committed by a small number of people. When you look at these people, they belong to criminal sub-cultures. They know about the penalties (including death), and accept them as part of the lifestyle. It takes very large changes in incentives to alter the behaviour (much more effective is re-socialising people out of the culture).
The rest is pretty random – disturbed young men, spur of the moment acts and so on. Again, not very amenable to changes in calculated incentives, but better managed by changing opportunities. Eg, stricter gun laws here in Australia have not done a lot for violent crime, but have markedly reduced suicide.
And then there’s accidents, mistakes….
February 22, 2011 at 4:15 am
DavidN
‘[S]tricter gun laws here in Australia have not done a lot for violent crime, but have markedly reduced suicide.’ – Hmm, I don’t know what the stats are for violent crimes are but we haven’t had a mass shooting since Port Arthur.
February 21, 2011 at 10:00 pm
A.F Walking
February 21, 2011 at 11:05 pm
Lones Smith
Sadly, yet another force for grade inflation in Texas…..
March 20, 2014 at 8:24 am
Maniprakash
Ah might want to amend that to say, in case I might NEED to shoot someone There have been a few times when the want rasied its ugly head the the NEED is always the deciding point. The need is self defense, of course. Only NEEDED to shoot once in the last 32 years. And if I never need to do so again, it will be just fine with me.
February 22, 2011 at 4:23 am
DavidN
Correction to earlier comment: Their actually has been one other mass shooting since Port Arthur with the Monash University shooting in 2002.
February 22, 2011 at 4:20 pm
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March 1, 2011 at 10:31 pm
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March 4, 2011 at 6:35 pm
James
“Now your decision to carry a gun is a trade-off between the chance of being shot versus the cost of being the victim of a crime. The people who will now choose to carry guns are those for whom the cost of being the victim of a crime outweigh the cost of an increased chance of getting shot.”
Huh? How does carrying increase the chance of being shot?
November 2, 2011 at 4:01 pm
Robert Johannesburg
I feel like this was fairly well reasoned and thought out. I appreciated that even though you were simplifying a complex matte, you recognized that in real life, it will never be that simple, and really each individual will react differently. I talked with my uncle, a criminal defense lawyer, about this and we both agree in our personal opinions, that more guns will actually probably increase gun violence. ( http://www.dubreuillawoffice.com )
January 14, 2012 at 10:11 pm
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