Deltoid

Steve D. Fischer writes:

There are two kinds of lies to worry about. The first is making up defensive gun usages (DGUs) which never occurred, or which did not occur within the 1 year time period. The second is concealing DGUs that did occur because you feared that your DGU might have been of question- able legality. We've talked at length about the second circumstance. Let's look only at the first, then.

Kleck reported 213 DGUs in a sample of 5,000. Assuming 59 million gun owners, that leads to about 2.5 million DGUs per year.

The NCVS estimated 80,000 DGUs in that same gun-owning population, which leads to about 88 DGUs in a sample size of 65,000. If the NCVS estimate were "correct" then Kleck should have only seen about 7 DGUs in his smaller sample size. Kleck's "excess" 206 DGUs must have been lying, then. This amounts to 4.1% of Kleck's sample.

But wait a minute, if both studies took good random samples of the population, then wouldn't we also expect 4.1% of the people who responded to the NCVS to make up DGUs also? There is no reason to assume that people who make up DGUs are not randomly distributed in the population, because roughly 48% of all households own at least one firearm. Where, then, are the (roughly) 2670 liars in the NCVS sample?

Good question. It is possible that 4% of the population make things up. If you ask them if they've used a gun for defence, they'll say "yes" and invent some details. If you ask them if they've seen a UFO, they'll say "yes" and invent some details. If you ask them if they've been burgled, they'll say "yes" and invent some details. So the 2670 liars in the NCVS sample would invent crimes, but not necessarily invent DGU as one of the details.

The NCVS interview is preceded by a phone verification of the location of the residence and persons who live there. This gives the respondents time to make up a good story, if that is their intent.

True, but a story about crime victimization does not have to include DGU.

In the Kleck poll, there in no pre-interview, and respondents must make up a lie contemporaneously, in such a way that the details will be relatively consistent.

Though not too consistent. The numbers saying somebody would have died, the number saying police knew of the incident, the number saying they wounded the perp, the number saying that they killed the perp are all impossible. I also note that in 85% of Kleck's cases the person involved was the person interviewed (rather than someone else in the household). As Kleck notes (p165) this is surprising since most households contain more than one adult. Kleck suggests that this is because people may be reluctant to "inform" on other household members. Alternatively, it may be because only made stuff up about themselves rather than others.