Overall, researchers found that the cameras did not have their desired impact on crime in parking facilities of the Washington Metropolitan Area Transit Authority rail transit system. Crime rates remained at pre-camera levels for both the treatment and comparison facilities for car-related crime, all crime, property crime, and violent crime.
Study 1
All Crime
Following the camera installation, the treatment facilities experienced a decrease of 6.42 incidents of all crime, whereas the comparison facilities experienced a decrease of 4.67 incidents of crime. Although all crime reduced by more than 11 percent in treatment facilities, compared with a 7 percent reduction in the comparison facilities, the difference was not statistically significant.
Property Crime
Camera installation did not have a statistically significant impact on property crime, as treatment facilities experienced an increase of 1.58 incidents of property crime following camera installation, while comparison facilities experienced an increase of 3.42 incidents of property crime. Although there appeared to be group differences, these differences were not statistically significant.
Violent Crime
Following camera installation, the treatment facilities experienced a decrease of 3.25 incidents of violent crime, while the comparison facilities experienced a decrease of 2.92 incidents during the same period. Although there were differences between the two groups, these differences were not statistically significant.
Car-Related Crime
Following camera installation, the treatment facilities experienced an increase of 1.25 incidents of larceny thefts, compared with an increase of 2.25 incidents at the comparison facilities. Although this indicated a difference between the two groups, the difference was not statistically significant.