"Violent offenders in State prison (50%) were less likely than drug (72%) and property (64%) offenders to have used drugs in the month prior to their offense."

Source

Mumola, Christopher J., and Karberg, Jennifer C., "Drug Use and Dependence, State and Federal Prisoners, 2004," (Washington, DC: US Dept. of Justice, Oct. 2006) (NCJ213530), p. 1.