With more parts of the country legalizing marijuana, it may be causing you to have questions about the legal uses of it. Even though it may be legal to use marijuana, it is still a substance that can impair your driving and cause you to get a DUI (driving under the influence) citation if caught. Here are some key things you need to know about DUI laws relating to marijuana use.
Determining If You Were Driving Under The Influence
Unlike blood alcohol levels that have a numerical value that can be measured during a traffic stop, marijuana does not have an immediately measurable indicator. Instead, there are multiple methods used to determine if a driver has been using marijuana, with each state having its own definition of what a marijuana DUI is.
Per se Laws
Your state may have per se laws regarding marijuana DUIs, which mean that if a driver has trace evidence of marijuana in their system, they can be charged with a DUI.
These laws will often require the driver to take a test to determine if there are metabolites in their body. These metabolites are compounds that are left over from marijuana use, and may remain in someone's system for days or weeks after they used the substance. Unfortunately, this is often enough to accuse someone of driving under the influence of marijuana.
Urine or Blood Concentration Levels
Some states use urine or blood tests to determine proof of marijuana impairment. There will be a legal threshold that needs to be reached as defined by each state, which is measured in nanograms of metabolites per liter of urine or blood.
Even if you are below the legal threshold in these tests, it's possible a prosecutor will use other factors to prove impairment.
Marijuana impairment can also be determined by the arresting officer based on your driving behavior. The cause for pulling you over may have been erratic driving, and can be combined with observations such as the smell of marijuana in the car, evidence of marijuana in the car, or telltale indications such as reddened eyes.
Defending A Marijuana DUI
There are many problems with being accused of a marijuana DUI. For example, the driver could have used marijuana in a legal situation out of state and still have the metabolites in their system when pulled over. If you are being accused of a marijuana DUI because test results found metabolites in your body, you should seek the help of a criminal defense attorney to defend you in court.