BASTROP, Louisiana. Police departments across the country have been using field drug tests to detect cocaine and methamphetamine. These inexpensive tests get countless convictions and guilty pleas. However, these tests often produce false positives. ProPublica found that the tests can produce false positives for over 80 legal substances, including methadone and common household products. It isn’t clear how many people have gone to jail as a result of these tests—which continue to be in use.

Individuals may learn that officers have evidence that they were driving while under the influence or that they are guilty of drug possession due to the results of these field tests. However, many individuals plead guilty without requiring the state to confirm their results in a crime lab. In fact, when the results of these tests are questioned, there are times where the field tests fail.

Because of the problems with field drug tests, it is important to carefully consider your options if you are facing a DWI charge or drug possession charge in Bastrop, Louisiana. The DWI and DUI criminal defense lawyers at Ross Downs understand the ways in which field tests fail individuals every day. Our firm will investigate the evidence gathered against you and require the state to validate any drug tests used. Don’t plead guilty if you are innocent. Contact Ross Downs.

The problem with field testing doesn’t end with inexpensive field chemical tests used at the scene. In Florida, investigators found that a drug sniffing dog was trained using a substance that had been falsely identified as methamphetamine. The substance had not been confirmed in the lab, so the dogs were trained to sniff out the wrong substance. ProPublica attempted to contact the police department where the dogs were trained. The department didn’t answer ProPublica’s request for information. It isn’t clear whether the dogs that were trained using the wrong substance remain on the force. If they are on the force, then it is possible that these dogs are identifying substances as drugs when the substances are, in fact, legal.

As it stands, there is little data about how many people have pleaded guilty to crimes they did not commit as a result of these faulty tests. Many police departments don’t track error rates or false positives on field tests, so it is hard to know.

At the end of the day, individuals who are facing criminal charges may not have the information they need to adequately fight their charges. They may be frightened into pleading guilty, unaware that the state has insufficient evidence. Public defenders are often overwhelmed with many cases and may not have the time to question state evidence. If you or a loved one is facing criminal charges, protect your rights. You have the right to remain silent and have the right to request the counsel of a DUI attorney. Visit to learn more about your rights.