by Marc J Victor on Aug. 24, 2017

Criminal Criminal  DUI-DWI 

Summary: Dobson v McClennen. On November 20, 2015, the Arizona Supreme Court decided Dobson v. McClennen which resolved the issue of whether medical marijuana cardholders; who legally use marijuana, remain subject to DUI prosecutions for merely having a detectable amount of marijuana in their blood.

Dobson v McClennen. On November 20, 2015, the Arizona Supreme Court decided Dobson v. McClennen which resolved the issue of whether medical marijuana cardholders; who legally use marijuana,  remain subject to DUI prosecutions for merely having a detectable amount of marijuana  (actually THC or its impairing metabolite) in their blood.  Therefore, last year, the Arizona Supreme Court determined the presence of the long lasting; but non-impairing metabolite was insufficient to constitute a DUI.  At the outset, it is important to note that I have previously written about why all DUI law is unjust and entirely unnecessary.  (Click here for my article on this point)   

Also, as I have written, the (A)(3) section of our DUI law, which is the focus of the decision in; Dobson v. McClennen, is the most unjust of all DUI law and should be immediately abolished in its entirety.  This section seeks to convict and punish people for DUI; without any evidence or requirement that the driver be impaired at all.  In other words, a person could risk conviction for the (A)(3) version of DUI while driving perfectly and not being impaired even to the slightest degree.


In Dobson v. McClennen, the Supreme Court, unfortunately, rejected the argument that a medical marijuana cardholder is absolutely immune from an (A)(3) DUI prosecution.  However, the medical marijuana user can now assert a defense that; the amount of marijuana (THC or its impairing metabolite) was insufficient to cause impairment at the time of driving. Since, as with all affirmative defenses, the defendant bears this burden to prove.  Also, it appears the defense may be able to argue that the level of impairment can differ from person to person.  As such, medical marijuana defendants in (A)(3) DUI prosecutions will now be required to obtain an expert to testify about whether the level was sufficient to cause impairment in this particular defendant.  

Although we are better off with this decision than without it, this decision partially highlights why the (A)(3) section needs to be abolished. First off, it seems a strange waste of resources to be litigating with experts whether some unspecified level of THC or impairing metabolite is; likely impairing as a defense to a crime that does not require impairment as an element of the crime. Second, Arizona has not established any presumptive level of impairment for THC or its active metabolite; so defendants are now tasked with the expense of litigation over the highly subjective and mostly irrelevant question of whether a person is likely impaired at some speculative level of THC or active metabolite at the time of driving.


Also, I expect this will be expensive and difficult to prove for defendants. Third, if there is impairment, the driver is guilty of the (A)(1) DUI rendering the (A)(3) section unnecessary for the medical marijuana user in any event.


Furthermore, our DUI laws have become an over-broad mess of unnecessary and expensive litigation.  Moreover, this case will add to that expense and mess.  All our justified fears about the dangers of drunk drivers can and should be addressed by our existing reckless driving statute and relevant felony statutes for cases where actual harm occurs.  Finally, if we simply abandoned our unjustified paranoia over the marijuana plant, it would be easy to see why the (A)(3) DUI section ought to be immediately abolished.  Until then, Dobson v. McClennen is a very minor step in the right direction; at least for medical marijuana users.


Attorney Marc J. Victor

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