In One Series of Studies of the Equity of Capital

In one series of studies of the equity of capital punishment, criminologists found:

A) blacks were more likely than whites to be executed for the same crimes
B) capital punishment is an ineffective deterrent against robbery
C) fear of the death penalty had discouraged them from carrying guns when they committed crimes
D) states with a death penalty have higher rates of murder at the time of robbery than states that do not have one