Standards for Intoxication for Using Marijuana When Driving

Even Legal Marijuana Use Can Result in a Charge of Driving Under the Influence

Illinois policy on marijuana is a little bit of a mish-mash. For years, state policy held that any trace of marijuana in the bloodstream or urine of a driver could support a charge of driving under the influence, or DUI. On the other hand, in recent years Illinois legalized medicinal use of marijuana. Legislation in the last five years has made an attempt to rationalize the conflict among the medical marijuana laws, recreational marijuana possession, and DUI laws. Two bills in particular have tried to address the apparent conflict between legal marijuana, illegal marijuana, and the state’s DUI laws. A certain amount of protection for holders of medical marijuana cardholders has resulted, while establishing standards for what constitutes DUI when using marijuana.

Two Recent Statutes Address Driving Under the Influence of Marijuana

In August 2013, the General Assembly passed a law that changed years of state policy. First, the law reversed a policy that held that any trace of THC, the intoxicating agent in marijuana, in the bloodstream or urine of a driver could serve as the basis of a DUI charge. The new statute provides that the so-called trace standard does not apply to anyone who is the registered holder of a medical marijuana card. However, the law does not protect even holders of registered medical marijuana cards who operate vehicles while under the influence of marijuana. In other words, the statute provides no defense to a charge of driving under the influence of marijuana, even if you have a medical marijuana card.

The statute also provides that standardized field sobriety tests, known as SFSTs, are legally recognized to establish probable cause for DUI arrests and to prove impairment at trial, but only for marijuana-related DUI stops, not for alcohol-related stops. Field sobriety tests, also called physical performance tests, were developed in cooperation with the federal government and law enforcement has used them for years in alcohol-related DUI stops. Critics dispute how effective they are in marijuana DUI stops. Oddly enough, no Illinois statute recognizes SFSTs for use in alcohol-related DUI cases.

Just as important is a law signed by Gov. Bruce Rauner in August 2016. The law decriminalized possession of small amounts of marijuana, treating such possession as a civil offense, punished by a fine rather than by criminal penalties. Possessing less than 10 grams of marijuana will now subject you to a fine of between $100 and $200, with automatic expungement upon payment of the fine.

In a critical provision, the statue does away with the trace standard, even for drivers who do not possess medical marijuana cards. This addresses a gap left by the 2013 standard that protected only medical marijuana cardholders from the trace standard. Perhaps just as important, the statute finally establishes standards for what constitutes a presumption of driving under the influence of marijuana, just as the law has done for decades for driving under the influence of alcohol. The 2016 law sets the presumption of DUI for marijuana at five or more nanograms of THC in the bloodstream, or 10 nanograms or more of THC in saliva.

The standards are important because marijuana use weeks before a stop for suspicion of DUI could result in a charge and conviction under the trace law. Only recent use of marijuana could result in a level of five nanograms of blood THC content or 10 nanograms of saliva THC content. As it is, the 2016 statute makes it much less likely that a casual marijuana user will meet the presumptive level of THC for DUI unless stopped soon after the marijuana use, or perhaps after fairly heavy marijuana use. Furthermore, red blood cells don’t absorb THC very well, nor does saliva. Finally, levels of THC in the bloodstream go up rapidly immediately after use, but also drop pretty quickly. Waiting a while to drive after marijuana use remains a good idea.

The new standards also place a burden on officers making suspected marijuana-use DUI stops. No device equivalent to portable alcohol Breathalyzers currently exists. While portable saliva testing equipment exists, saliva testing is not reliable. Also, it is not clear how many police departments in Illinois, if any, own portable equipment to test for THC levels in saliva, regardless of the unreliability of such tests.

Despite New Standards, Penalties for Driving Under the Influence of Marijuana Are Steep

Medicinal use of marijuana is legal in Illinois for registered holders of a medical marijuana card, and possession of small amounts of marijuana has been decriminalized—and incoming Gov. J.B. Pritzker has vowed to push for full legalization. More permissive laws and attitudes about use and possession, however, do not mean more leniency for driving while intoxicated by marijuana. Operating a motor vehicle under the influence of marijuana remains against the law, with severe penalties for doing so.

To legally use marijuana—not simply possess it—a person must be at least 18 years old, have a written certification of a permitted illness from an Illinois doctor, and register with the state Department of Public Health. The DPH will issue a medical marijuana identification card, and the person’s driving record will include a notation regarding his or her medical marijuana status.

Permission to legally use marijuana does not protect a cardholder from legal consequences of driving under the influence, however. A cardholder stopped for suspicion of driving under the influence must submit to field sobriety testing, and refusal to do so will result in a license suspension. A conviction for driving under the influence of marijuana will result in the revocation of the driver’s medical marijuana card.

Naturally, the same penalties for driving under the influence of marijuana apply to anyone else convicted of a DUI. These penalties include:

  • First-offense for driving under the influence of marijuana is a misdemeanor, punishable by a maximum of a year in jail and a maximum fine of $2,500.
  • Second-offense for driving under the influence of marijuana also is a misdemeanor and carries a maximum punishment of a year in jail and a fine of $2,500.
  • Third-offense for driving under the influence of marijuana is a felony, carrying maximum penalties of three years in prison and fines of $25,000.

If You Are Facing Marijuana-Related DUI Charges in DuPage, Kane, or Cook County, Consult the Criminal Defense Attorneys of Martin & Kent, L.L.C.

If you are facing charges of driving under the influence of marijuana, call the criminal attorneys of Martin & Kent, L.L.C. They have a combined 45 years of experience, including time as felony prosecutors. They will mount a tough and aggressive defense, and are committed to winning at trial if necessary. For a consultation contact us 24 hours a day at (630) 474-8000. We serve DuPage, Kane, and Cook Counties.



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