For a variety of specific crimes, researchers have produced data indicating more lenient treatment of black offenders than of white offenders. For homicide, this is partly attributable to the fact that homicides tend to be intraracial. With drug offenses, black drug traffickers are sometimes perceived as "victims" of America's drug problems. Different minority races have historically been associated with different drugs, for example, the Chinese with opium, southern blacks with cocaine, and Mexicans with marijuana. While these races were once portrayed as symbolic villains, they have since the 1960s been counted with the mainstream as victims, while big drug dealers have become the new symbolic villains. While this may suggest an economic rather than racial hierarchy, the peak years of lenient treatment towards ordinary non-white drug offenders (1969-1973) were also the years of the most severe sentences towards non-white big dealers. 10 notes, 6 tables.