How long does Marijuana stay in your system

Surprise, surprise another article recently came out in the Seattle Times describing another DUI arrest in King County. However unlike the previous dozen or so articles, this one dealt with a Marijuana DUI case. The reason I bring up this article and the Marijuana DUI Case is involved was something that the driver said to the arresting officer. I guess when the arresting officer was contacting the driver, the driver said he had smoked marijuana, and it was no big deal because he could smoke as much as he wanted because it is legal now. Well unfortunately for this guy that is not true when it comes to driving with Marijuana in your system.

So this got me thinking. How many people actually are aware of how long Marijuana stays in your system. Probably not a lot. I can’t tell you how many people have asked me in the past few months about Marijuana use and DUIs. Especially with the legal limit for Marijuana being so low in my opinion.

When it comes to Marijuana staying in your system there is a general consensus that the effects of it will fade relatively quickly, but it will actually stay in your system for quite some time. To put it simply the more you smoke, the longer it will stay in your system. Additionally the more fat build up you have in your body, the longer it will stay in your system.

Now there are generally two types of ways to test for Marijuana in your system. Urine, and by a blood test. For the purposes of DUI arrests blood tests are used. The good thing about a blood test is the active ingredient of marijuana, THC only stays in your blood for a short time. If Marijuana is smoked then it will rapidly enter into the blood stream. If it is ingested it can take some time. Possibly 1/2 hour or so.

Now the metabolites for the THC which is the form Marijuana takes when it becomes metabolized get stored in fat cells, and is gradually eliminated from feces and urine. That is why urine tests are more effective in testing for Marijuana, because metabolized THC will stay in your system for quite some time.

If have seen some studies that show some THC metabolites have a half life of 20 hours, while some can stay in the body for two weeks. Additionally some studies have shown the regular Marijuana users can still test positive for the THC metabolite 45-90 days after. Depending on the body type, and how much was smoked or ingested.

So what is the bottom line. If you’re under arrest for a Marijuana DUI and a blood test is administered it really is going to depend on how much Marijuana was smoked or ingested, and whether there are any active ingredients still in the system. Since the metabolites are generally not considered to affect a persons ability to drive you probably should be too worried about testing positive for those. Unless your testing for an employer in which case most employers have zero tolerance, and they will see the metabolite.

About the author: Matthew Leyba is a DUI Lawyer in Seattle, WA. He is rated as a Top DUI Attorney in Seattle by Avvo, and was recently named a Rising Star in the area of DUI Defense by Super Lawyers Magazine. An honor less than 2.5% of all Attorneys in Washington State receive.