"Everything people used to say about marijuana is true of angel dust." So claimed Robert DuPont, director of the National Institute on Drug Abuse, in 1977.
DuPont's comment is worth revisiting now that Washington, D.C.'s police chief is citing "angel dust"—the veterinary anesthetic phencyclidine (PCP)—as an explanation for his city's rising homicide rate. End-of-the-year figures show that homicides in D.C. jumped 12 percent between 2001 and 2002, and Police Chief Charles Ramsey says increased PCP use is one reason.
"It's really alarming," Ramsey told The Washington Times in December. "We are seeing PCP use on the rise, and when you couple that with the number of weapons on the streets, we are seeing an increased number of homicides."
Robert DuPont's 1977 warning about PCP suggests one reason to be skeptical of this theory: Back in the 1920s and '30s, police spoke just as confidently about a link between marijuana and violence. The Federal Bureau of Narcotics portrayed marijuana as "the killer drug," giving men "the lust to kill, unreasonably and without motive."
One of the first such reports came from a Texas police captain who claimed habitual marijuana users "become very violent, especially when they become angry, and will attack an officer even if a gun is drawn." He added that they "seem to have no fear," are "insensible to pain," and display "abnormal strength," so that "it will take several men to handle one man."
This description is eerily similar to contemporary stories about PCP users, whose rage and superhuman strength are said to resemble those of the Incredible Hulk. Of course, the fact that the authorities were wrong about marijuana does not mean they are wrong about PCP. But a careful examination of the evidence provides little support for PCP's reputation as a Dr. Jekyll potion that unleashes the monster within.
In a 1988 review of 350 journal articles on PCP in humans, the psychiatrist Martin Brecher and his colleagues noted that high doses of PCP can produce "severe agitation and hyperactivity," along with "cognitive disorganization, disorientation, hallucinations, and paranoia." Combined with the drug's anesthetic effect, which makes users less sensitive to pain and therefore harder to restrain, such acute reactions have contributed to PCP's fearsome image.
Yet in their search of the literature, Brecher and his co-authors found only three documented cases in which people under the influence of PCP alone had committed acts of violence. They also noted that between 1959 and 1965, when PCP was tested as a human anesthetic, it was given to hundreds of patients, but "not a single case of violence was reported."
Brecher and his colleagues concluded that "PCP does not live up to its reputation as a violence-inducing drug." That does not mean PCP users are never violent. But when they are, their behavior cannot be understood as a straightforward effect of the drug.
"Research on the nexus between substance use and aggression," notes the criminologist Jeffrey Fagan, "consistently has found a complex relation, mediated by the type of substance and its psychoactive effects, personality factors and the expected effects of substances, situational factors in the immediate settings where substances are used, and sociocultural factors that channel the arousal effects of substances into behaviors that may include aggression." The pharmacologist John P. Morgan and the sociologist Lynn Zimmer put it this way: "No drug directly causes violence simply through its pharmacological action."
This point is obvious when we consider alcohol, the drug that is most strongly associated with violence. The fact that some people get into fights after drinking does not mean alcohol makes them behave that way. Variations in responses to alcohol across individuals, cultures, and situations show that drinking does not necessarily lead to bloodshed.
Another complication is that drug prohibition creates a black market in which disputes are resolved through violence. An analysis of New York City homicides committed in 1988 and identified as "crack-related" found that 85 percent grew out of black-market disputes. Only one homicide out of 118 involved a perpetrator who was high on crack.
Such findings put crime statistics in a different light. "In cases where we know or suspect a motive," reports a D.C. police spokesman, "over one-third of the killings are drug-related." If so, that is an indictment of the drug laws, not PCP. The Saint Valentine's Day Massacre could be called "alcohol-related," but not because Al Capone's thugs were drunk.
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