A forensic lab test for THC is one of the biggest areas where things can go wrong. There are three THC variants that we know of at this time. Delta-8 and Delta-11 variants are legal and don’t impair driving. The Delta-9 variant is currently illegal in Texas and potentially impairs driving. The main problem is the Delta-8 variant and the Delta-9 variant look almost the same even with the best testing methods. Chemist tell me it’s like your left and right hands. If you have your hands facing away from you, they look like a mirror image of each other. If you hold your palms together, they look the same.
Also the type of test performed has a big impact on results. There are two types of chemical testing for unknown substances generally accepted. These are Gas Chromatography Mass Spectral Analysis and Liquid Chromatography Mass Spectral Analysis. The biggest difference between the two is one turns the sample into a gas for testing and the other blends the sample with a liquid for testing. Gas Chromatography is easier for most chemist to understand and perform. Most chemist agree that the best analysis for a blood sample for someone arrested for drunk driving due to alcohol is Gas Chromatography. This is because alcohol is considered too volatile for Liquid Chromatography. Yet most chemist agree the Liquid Chromatography is the best analysis for a blood sample for other substances besides alcohol.
There’s a big problem with testing THC with Gas Chromatography. The act of heating the blood sample to turn it into a gas also turns a Delta-8 variant into a Delta-9 variant. So the police can arrest someone for drunk driving and get a blood sample. They send the blood sample to a crime lab with a report saying the sample came for someone suspected of drunk driving due to alcohol. So the chemist performs a Gas Chromatography analysis and suddenly ALL of the THC in the blood shows up as the illegal Delta-9 variant. Even if the blood/alcohol level in the sample was below the legal limit, a prosecutor could still charge the driver with a crime due to the combination of alcohol and THC Delta-9 variant that the testing created.
This is not the only way that a THC Delta-8 variant gets turned into a THC Delta-9 variant. Chemist say heating a sample to 130 degrees will do it. That’s possible even with Liquid Chromatography testing. It’s also extremely likely with a sample left in a vehicle. The Texas Department of Public Safety says the temperature inside a vehicle on a 90 degree day can soar past 130 degrees in less than thirty minutes. This is what’s called “The Greenhouse Effect” where sunlight passing through glass heats up trapped air. It’s possible for the temperature inside a vehicle to reach up to 170 degrees. That alone could turn a THC Delta-8 variant into a THC Delta-9 variant. This is just one reason it’s good to have a lawyer who has a basic understanding of the science behind chemical sample testing.
Contact us today for a free consultation and let us help you through the lab testing process for your criminal defense case.