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Does marijuana in your blood turn a fatal accident into a felony?

San Jose, CA |

I have a medical marijuana card. I never smoke before driving, however, I am worried that if I get into an accident and someone is hurt or even killed, that I could be blood tested then charged with manslaughter because they find traces of THC. What can I do to protect myself?

Attorney Answers 8

  1. Best answer

    Even without any intoxicant in the blood, the driver of a vehicle involved in a fatal accident can be charged with a felony vehicular manslaughter, depending on the level of negligence alleged, because gross negligence makes the charge more serious. Yes, there are versions which take alcohol or drugs into account. This is a complicated area in general because the studies for marijuana are not as advanced for alcohol as far as impairment. It is possible to get charged with a DUI based on marijuana but can be more difficult to prove. Consult with an experienced DUI attorney if you ever get charged with one because the evidence is quite different from an alcohol DUI.

  2. Thanks for trying to be responsible. You can choose not to drive after using weed, but that's not a very good answer because it stays in your system for a long while and some states - even where legal for recreational use - might try to use trace amounts, if sufficient under their law, to convict you of DUI even if you might not have been impaired. In California, it is of course unlawful to drive while impaired by any drug. The issue is impairment and how it's figured. That's when a good attorney experienced in marijuana DUI comes in. Anyway, read this article:

  3. If this relates to a real crime you should stop posting details of the arrest online and retain an experienced criminal defense attorney to address your husband’s case. If this relates to a concern about the consequences of driving while impaired, simply refrain from driving.

    Stew Crawford, Jr., Esq.

    Crawford Law Firm
    A Full Service Law Firm Serving Pennsylvania & New Jersey

    Philadelphia Area Office
    223 North Monroe Street
    Media, Pennsylvania 19063


    All information provided in this comment is intended for informational purposes only and does not, by itself, create an attorney client relationship. Without the benefit a personal consultation to exploe all of the facts of your legal problem, the information in this posting may be inaccurate and for that reason it should not be relied upon. If you wish to consult with an attorney, or have any questions concerning this comment, please feel free to contact our offices through any of the above contact sources.

  4. Don't drive under the influence. Just because "medical marijuana" is legal in the State of California, doesn't mean you should be driving. Now on the other hand, if you last smoked a joint 10 days ago, get into an accident and your blood reveals some level of THC, that doesn't you're going to be charged with a crime. It depends on a number of factors: your subjective symptoms [bloodshot or watery eyes, your eyes reaction to stimuli, inability to walk steadily] and objective signs of intoxication [performance on field sobriety tests], as well as the results of a drug recognition evaluation performed by the police officer at the scene. Of course the amount of THC in your system is important as well. Its easy - if you don't think you should be driving, then don't.

  5. the short amswer ia stop smoking. but yoy are right mj shoes up in tests
    like urime days weeks later. however tch generally dissipates.

  6. As pointed out if you kill someone while driving you can be charged criminally regardless if THC is found on a blood test, so drive carefully. As for protecting yourself against a DUI manslaughter charge, there's nothing you can do except not use your medicine. This is likely not an option for you given your health condition. As a matter of science and research marijuana DUI's are bogus in that marijuana (per available studies) makes you a more cautious driver (see: and: ).
    That said, District Attorney's, who invariably are cannabis phobic narcs, don't care what the science says, they will seek to charge you and throw you prison for as long as possible. Given that, you are certainly cautioned to cease using your medicine well before operating a motor vehicle. To be extra cautious you may want to give up using your physician approved medical treatment or cease driving altogether. You can continue to medicate and get transported via limo, cab, bart, ferry, bus, train, plane, or hitchhike. Best of luck.

  7. Your instincts are right. Dont smoke and drive. Then you got nothing to worry about.

  8. The real short answer is that anything that impairs your driving [within the definition of impairment in this state, which is often misunderstood] can make your driving illegal, and if you kill someone while impaired, it can be manslaughter or 2d degree murder, depending on many things. The fact that something is legal to consume does not mean you can drive under its influence - it has been held that driving under the influence of kava-kava is illegal here, and that's just an herb with minor effects. But the fact that mj shows up in your system for a long time does not mean its impairment effects last a long time - they do not.

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