"The 'factual' assertion that student drug testing is an effective deterrent has been proved unsupportable, and indeed false, by empirical and anecdotal evidence. This evidence reveals that student drug testing does not change student drug usage in any way and may, instead, cause more harm than good to the educational function. Students escape detection by changing their drug of choice or changing the time when they indulge. They find ways to mask or change the test results, sometimes dangerously so. As a last resort, students turn to alcohol, clearly not a result that schools would have hoped to happen or what they would have encouraged.88 And the results of even the advocates’ favorite studies show no long-term deterrence."

Source

Stuart, Susan P., "When the Cure is Worse than the Disease: Student Random Drug Testing & Its Empirical Failure," Valparaiso University Law Review (Valparaiso, IN: Valparaiso University Law School, 2010), Volume 44, Number 4, p. 1075.
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