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False Positives Lead To Big Consequences, Part Two

Posted by Aaron J. Wolff | Jul 18, 2016 | 0 Comments

The New York Times Magazine recently ran an article about the quick roadside chemical tests that are often used by law enforcement officers to determine if a substance is an illegal drug or not.

This is a two part post. To read the first part click here.

Amy Albritton had a felony conviction on her record thanks to a color changing chemical test that a police officer administered on the side of the road in Houston, Texas. She had served time in jail, lost her job and her home -- and she was innocent. The test had returned a false positive result. Based on that test and the advice of her public defender, she had plead guilty to a charge of drug possession.

The roadside chemical tests first came into use in the late 1960's. According to the Times, the test that is used by the Houston police department, is a "single tube of a chemical called cobalt thiocyanate, which turns blue when it is exposed to cocaine." However, other things such as acne medications can also produce the same blue color, it's not exclusively just the illegal substances that cause the color change. There are "[o]ther tests [that] use three tubes, which the officer can break in a specific order to rule out everything but the drug in question." However, this test has its drawbacks as well as because "if the officer breaks the tubes in the wrong order, that, too, can invalidate the results." In addition other factors can affect the tests, such as the temperature and inadequate lighting.

The Times stated that "[t]here are no established error rates for the field tests, in part because their accuracy varies so widely depending on who is using them and how." A re-examination of evidence in Las Vegas found a 33% error rate in tests for cocaine between 2010 and 2013. Florida authorities also found that "21 percent of evidence that the police listed as methamphetamine after identifying it was not methamphetamine, and half of those false positives were not any kind of illegal drug at all."

Interestingly, in most jurisdictions these tests are actually inadmissible as evidence at trial. Prosecutors have to "present a secondary lab test using more reliable methods." However, despite this many cases, like Albritton's, are plead out on this evidence. The Times reported that "[i]n 2011, RTI International, a nonprofit research group based in North Carolina, found that prosecutors in nine of 10 jurisdictions it surveyed nationwide accepted guilty pleas based solely on the results of field tests." Nowadays, most criminal cases are plead out. For example, in Harris County, where Albritton was charged, "99.5 percent of drug-possession convictions are the result of a guilty plea."

So what happens when lab results later show that the roadside test produced a false positive? According to the Times, that is where the Harris County district attorney's conviction integrity unit comes into play. These units are made up of prosecutors who "re-examine convictions in light of new evidence, often in the form of previously unavailable DNA tests." In 2014 the head of the unit, Inger Chandler, was informed by a reporter about a "series of unusual exonerations coming out of the Texas Court of Criminal Appeals." The cases the reporter had looked at had been reversed because the drugs were found by a lab to not be drugs. In the cases, "[t]he laboratory results came after defendants had already pleaded guilty." The reporter wanted to know if there were other similar cases. Chandler began to look into the matter.

Were there other cases where the roadside test had been proven wrong by lab work? To find out what happened and whether Albritton was exonerated, read on.

About the Author

Aaron J. Wolff

A former DUI prosecutor, Aaron Wolff has over 18 years of experience in representing people accused of DUI and is recognized as one of the leading defense lawyers in Washington State. His relentless and passionate advocacy has lead to superb ratings and outstanding reviews from former clients.


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