Though medical marijuana is legal in Arizona, driving while under the influence of drugs is not. As a result of evolving laws across the country, officers began implementing roadside tests for marijuana that are similar to the breathalyzer test for alcohol. The problem with these tests — as well as roadside tests that measure actual substances in the body — is their inaccuracy.
Courts throw out convictions based on flawed drug tests
In addition to the new mouth swabs that officers are using to test for marijuana in states like Arizona, some officers also use field kits to test substances. In theory, if the substance is illegal, it will turn a particular color.
In Nevada, subsequent laboratory tests of a substance that was previously believed to be cocaine turned out not to be illegal. This resulted in five convictions being overturned. These defendants had pled guilty to drug charges to avoid potentially harsher sentences if they lost at trial.
Nevada was not the only state to throw out wrongful convictions. Five convictions in Oregon were also overturned, and over 250 convictions were thrown out in Texas.
Problems with the tests
The roadside drug tests are appealing to cops because they are convenient and affordable at only $2 per test. Not surprisingly, these cheap tests often show false positives when legal substances turn the wrong color. Another problem is that officers often misinterpret the tests. Some courts have barred these tests as evidence because of their inaccuracy, but many district attorneys nonetheless use the tests to obtain guilty pleas from defendants.
What to do if you are arrested for drug possession
Studies have found that the roadside drug tests are good enough to give an officer probable cause to make an arrest but not enough to prove a person guilty at trial. Unfortunately, many individuals think that the cops have them dead to rights if a drug test is positive for an illegal substance and they enter plea deals prematurely. If you are arrested on suspicion of drug possession, do not say anything to the police. Instead, speak with a criminal law attorney as soon as possible.