Deltoid

Yes, the measure of shooting DGUs is inaccurate because of the small number (16) of sample cases. A 95% confidence interval is 100,000 to 300,000 criminals are shot by armed citizens each year.
However, even allowing for the inaccuracy, the number does not seem possible.

Eugene Volokh writes:

(2) Could it be that this figure is not that far off the mark considering that a number of career criminal-career criminal confrontations may accurately be called "defensive gun use"?
Criminals, after all, sometimes have to defend themselves, too, and they might be quite honest when they say they were acting (in that situation) defensively. Of course, some might be less thrilled by those DGUs than by "honest citizen" DGUs; but the same overestimate may take place in the NCVS --- it may be that many of the robberies and assaults counted by the NCVS, for instance, are basically bad guys robbing/assaulting bad guys. Am I missing something?

This does not seem likely. The number is greater than the NEISS estimate of all shootings (criminal, justified, suicidal and accidental). Kleck has used an estimate of a 15% fatality rate from defensive shootings. 200,000 such shootings would therefore result in 30,000 shooting deaths from self-defense shootings, which is much more than the total for all gun homicides, criminal or lawful.

(3) Finally, one thing that does make me doubt that the respondents were lying is that --- as Kleck points out --- the great majority of the reports did not involve the gun being fired. Why would someone lie in this sort of survey? Presumably, I'd guess, to make themselves seem macho to the interviewer (pointless, of course, but possible).

Some may believe that it is a citizen's duty to fight back against crime, just as it is to vote. I believe that surveys tend to overstate the number that vote by a few percent.

But if so, why would a lot of the liars invent such humdrum incidents?

This seems to be buttressed by the other details; in most cases, the offender was said to be unarmed; in very many, there was no threat or attack by the offender; in 47% of the cases there was only one offender. Again, not very macho stuff.

It may be that they are describing real DGUs but changing some of the details as in who it happened to and when it happened. There is support for this in that Kleck found that 85% of the time the gun user was the respondent rather than someone else in the household. Since the respondent was randomly chosen from within the household the correct number should have been 51% (the average household size is slightly less than 2). Kleck found this surprising and decided that it was because the respondent was concealing DGUs by other household members. In table 1 it would appear that he multiplies the numbers from the other surveys that were household based by 1.7 to compensate for this under counting.

Alternatively, a respondent making up a DGU, or describing a friend's DGU as if it happened to someone in the respondent's household will tend to make him or herself the defensive gun user. It may be that of those that reported a DGU to Kleck, 70% made it up or changed the user to him or herself. That would leave 15% where the respondent was the user and 15% where it was someone else in the household.

There is a similar anomaly with when the incident occured. You would expect 20% of the DGUs to have occured in any one of the five years. But twice as many (40%) occured within the last year.