Aggravated Assault

Robbery

Property Crimes

Auto Theft

Burglary

Larceny

–2.63

(0.45)**

–3.02

(0.53)**

–1.13

(0.27)**

0.25

(0.45)

–1.80

(0.30)**

–0.84

(0.30)**

–1.92

(0.20)**

–2.58

(0.22)**

–0.01

(0.13)

–0.49

(0.19)*

–2.13

(0.14)**

–0.73

(0.13)**

–2.02

(0.57)**

–0.44

(0.79)

–1.33

(0.29)**

1.62

(0.54)**

–2.50

(0.34)**

–1.27

(0.34)**

–0.65

(0.20)**

–0.88

(0.26)**

–0.81

(0.11)**

0.57

(0.19)**

–1.99

(0.13)**

–0.71

(0.13)**

bUsing the revised new data set, which contains observations, 1977-2000, even though the estimates in this row use data only through 1992.

NOTE: All samples start in 1977. SE = standard error. Standard errors are in parentheses, where * = significant at 5% and ** = significant at 1%.

stantial changes to the results. For example, right-to-carry laws are estimated to decrease murder by about 4 percent using the revised specification, but about 8 percent using the original specification. The estimated effects for the eight other crime categories decrease between 2 and 6 points when moving from the original to the revised specification.

We also estimate the trend model extending the sample to 2000 (row 1, Table 6-6). Relative to the estimates in row 0 (using only data to 1992), the estimates are mostly smaller but remain negative and statistically significant. Thus, the trend specification continues to show reductions in the rate of growth of crime following right-to-carry passage.

To explore why the updated dummy variable and trend models give conflicting results, we do two things. First, we estimate a more flexible year-by-year specification, a variant of Model 6.1, the dummy variable model. Second, we reanalyze the trend model (Model 6.2) by varying the number of years after the law’s adoption to estimate its effects on crime. In each of these cases, we use the revised new Lott data through 2000 and we include the original controls used by Lott and Mustard (1997). In each of these cases, except for sampling variability, the changes should not affect the results if the trend model in equation 6.2 is properly specified.



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