The use and possession of drugs in the United States is problematic, but a bigger problem that people are facing is the $2 roadside drug test kits used by cops that can lead to false convictions.
In 1973, Richard Nixon established the DEA, declaring “an all-out global war on the drug menace,” which led to a pair of California inventors patenting a disposable comparison detector kit. After trying out these drug kits, police departments across the country ordered the field tests because of their simplicity and quick results.
And yes, the small and cheap drug tests seem straightforward—but they come with multiple inefficiencies.
The kits contain a single tube of cobalt thiocyanate, which turns blue if exposed to cocaine. However, it also turns blue when exposed to methadone, certain acne medications, household cleaners and up to 80 other compounds.
And that’s not the only flaw with this test. Officers are not educated on how it works, often misinterpreting which colors the test is indicating and misunderstanding the results.
The National Bureau of Standards has even said that the kits “should not be used as sole evidence for the identification of a narcotic or drug of abuse.” Chemists themselves have stopped relying on color tests, preferring to use spectrographs, which give better and clearer results. The Department of Justice has also said that field tests “should not be used for evidential purposes.”
And indeed, the field tests in use today remain inadmissible at trial in nearly every jurisdiction; instead, prosecutors must present a secondary lab test using more reliable methods.
But most drug cases are decided outside of the courtroom due to plea-bargaining, according to reports from the New York Times. This means that individuals make deals outside of the courtroom in order to lessen their sentence—without ever going to trial.
Every year at least 100,000 people in the U.S. plead guilty to drug-possession charges that rely on field-test results as evidence. RTI International, a non-profit organization in North Carolina, did a study in 2011 that showed nine out of 10 people nationwide accepted guilty pleas based solely on field tests. At that volume, even the most modest of error rates could produce thousands of wrongful convictions.
A re-examination of these field tests in Las Vegas showed that from 2010 to 2013, 33 percent of cocaine arrests were due to false positives from field tests. In Florida, lab data showed that 21 percent of evidence police identified as methamphetamine was not actually meth—with half of those false positives proving to be unrelated to illegal drugs.
According to the New York Times, even trained lab scientists struggle with confirmation bias—the tendency to take any new evidence as confirmation of expectations—and police officers can see the tests as affirmation of their decisions to stop and search a person.
The environment can also play a factor in the inaccuracies of the drug testing kit.
If weather is cold, it slows the coloring process of the test. If the weather is hot, it speeds up the coloring process or prevents it from happening completely. If the officer is in an area with poor lighting, including street lamps and/or flashing police lights, it could ultimately cloud the officer’s judgment, leaving he or she unable to distinguish differences between the colors.
The Justice Department issued guidelines in 2000 calling for test-kit packaging to carry warning labels, including a statement that users of the kit should receive appropriate training in its use and should be taught that the reagents can give false-positive, as well as false-negative, results.
However, the New York Times investigated three of the largest manufacturers—Lynn Peavey Company, the Safariland Group and Sirchie—and found that none had printed warnings on their tests.