use (1989:57): “Because anyone using drugs stands a very good chance of being discovered, with disqualifications from employment as a possible consequence, many will decide that the price of using drugs is just too high.”
The American Management Association reports that the proportion of its 700,000 members operating drug testing programs rose from 21 percent in 1987 to 81 percent by 1996 (American Management Association, 1999). Similar trends are reported by the nation’s largest companies. The percentage of medium-to-large firms using some form of drug testing nearly doubled from 32 percent in 1988 to 62 percent in 1993 (Hartwell et al., 1996). However, despite these trends among larger firms, small businesses do not require drug testing.
According to the National Household Survey of Drug Abuse in 1994, one third of adults in the workforce reported that their employers operate a drug testing program. About 14 percent of the employed respondents reported that their employers tested only at hiring, whereas the remainder (18 percent) reported that their firms conducted random postemployment testing (Hoffman and Lavison, 1999). Under a random testing protocol, employees are automatically selected for periodic testing in the absence of any dangerous incident or individualized suspicion. Some employers limit the classes of employees subject to random testing to “safety-sensitive” positions, requiring only “for-cause” testing for other employees. Presumably, a large proportion of employers conduct for-cause testing on the basis of an injury or suspicion of intoxication or impairment. Forcause testing is uncontroversial because it is generally perceived as fair and most likely helps to deter workers from becoming intoxicated on the job. Because random testing is the only policy likely to exert a significant deterrent effect on whether workers continue to use drugs at all, this discussion focuses exclusively on this practice.
In the public sector, drug testing practices are circumscribed by the Fourth Amendment’s ban against unreasonable searches. In general, random testing of public employees is permissible if the program applies only to employees holding safety-sensitive positions or perhaps to positions implicating the integrity of the agency’s mission. Otherwise, the courts have ruled that random testing constitutes an unreasonable invasion of employee privacy (Harmon v. Thornburgh, 878 F 2d 484 (D.C. Cir. 1989) cert, denied 493 U.S. 1056, (1990)).
In the private sector, the law generally leaves employers free to adopt whatever testing policy they choose. Federal law encourages drug-free workplaces, and drug testing is explicitly authorized under the Americans with Disabilities Act. (This act prohibits disability-based discrimination against persons with histories of drug addiction as long as they are not currently using illegal drugs.) The practice of drug testing is unregu-