"Drug offenses were the second most common federal crime. In fiscal year 2012, 26,560 offenders were convicted of a drug crime, the majority involving the manufacture, sale, or transportation of a drug.5 Of these, 1,451 offenders were convicted of an offense involving simple possession of a drug.
"Offenses involving cocaine, in either powder form or base (crack) form, were the most common drug crimes, accounting for 38.0 percent of the offenders sentenced under the drug guidelines. These cases were almost evenly split between the two forms of the drug until fiscal year 2008. After that year, crack cocaine cases began decreasing steadily from 24.4 percent in fiscal year 2008 to 13.8 percent in fiscal year 2012. After cocaine cases (powder and crack cases combined), marijuana offenses were the next most common, representing 27.6 percent of all drug crimes. In fact, marijuana cases were more prevalent than either crack cocaine or powder cocaine cases individually. Drug offenses involving methamphetamine represented 19.5 percent of all drug crimes. Heroin cases were the least common of the major drug offenses, accounting for 8.6 percent of all drug crimes.
"Most drug offenders were United States citizens, but the percentage of drug offenders who are citizens varied widely depending on the type of drug involved in the offense. For example, 97.8 percent of crack cocaine offenders were United States citizens, while only 51.1 percent of marijuana offenders were United States citizens."


US Sentencing Commission, "FY 2012 Overview of Federal Criminal Cases" (Washington, DC: USSC, July 2013), pp. 6-7.