DUI under the influence of Marijuana


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Driving under the Influence of Marijuana

DUI Under the Influence of Marijuana

DUI under the Influence of Marijuana is an increasing problem, in Orange County, and elsewhere.  Because the laws measure for THC, the active ingredient in Marijuana, and because there is no legal limit that is considered “safe to drive” under, mainly because of a lack of studies on the subject, having marijuana in your system can be illegal.

Add to that the fact that marijuana can stay in your system as long as a month, and being arrested for an Orange County Marijuana DUI can be a major problem.

What is Marijuana?

Marijuana is a plant that, as of 2017, you can now legal to possess or consume in California for personal use.  Technically it is any cannabis plant, or any part of any such plant, and is also called weed, herb, pot, grass, bud, ganja, Mary Jane, and a vast number of other slang terms. Because marijuana is legal does not mean, however, that it is legal to drive with it in your system.  That remains illegal.

What is the legal limit for driving under the influence of Marijuana?

Unlike alcohol, which is illegal to drive above a .08% blood alcohol level, there is no legal limit, safe limit, or studied limit that creates a line between you being allowed to drive or not drive with marijuana in your system.

In Colorado, which made marijuana legal before California did, the law currently specifies that drivers with five nanograms of active tetrahydrocannabinol (THC) in their whole blood can be prosecuted for driving under the influence (DUI).

However, no matter the level of THC, law enforcement officers base arrests on observed impairment. And, as many scientific experts will say at trial or upon reviewing the literature, the five nanogram limit does not seem to be based upon any scientific testing or field testing.

How do the police test for marijuana DUI?

For alcohol, your performance on field sobriety tests, specifically the standardized tests given by a Drug Recognition Officer (DRE), can be used to determine whether or not you are under the influence.

Marijuana is supposed to have the following reported symptoms:

  • Sleepiness, or drowsiness
  • Memory impairment
  • An altered sense of time
  • Increased appetite
  • Mood changes

The Orange County Crime Lab is responsible for testing for marijuana, and they recently did a larger scale study of the drug and driving than had ever been done in the past.  The studies focused on marijuana impairment with existing field sobriety tests that were created for alcohol impairment detection. They used statistics from existing

Marijuana Field Sobriety Testing

Horizontal Gaze Nystagmus (HGN): Most subjects didn’t have HGN, but some did.

Lack of Eye Convergence: 86% of subjects had lack of convergence.

The Walk and Turn Test (WAT): Results varied depending on if a Drug Recognition Expert (DRE) or non-DRE officer administered the testing. Over 86% of subjects had 2 or more clues.

One Leg Stand (OLS): About 36% of subjects had 0 or 1 clue. There was no correlation with THC level.

Rhomberg Test: 46-48% of subjects were within +/- 5 seconds of estimating time passed. More people underestimated than overestimated.

Finger to Nose: No correlation with THC level.

This study is based on arrest and DRE reports, so there is no data on THC levels from people who were not arrested, based on good FST performance.

There is no data on sober FST performance, so its hard to say how significant the performances are with THC on board.  It’s time to have a large scale study on THC or Marijuana and DUI.

If you have a Marijuana DUI case in Orange County, contact our firm.  We have the experience, and knowledge, to help. 

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