Most tokers know and agree that baked driving is not a good idea. Your reaction times and motor skills when stoned are not at their sharpest, and this is far from ideal when operating a heavy lump of metal at breakneck speeds.

For this reason, driving while high is a serious criminal offense in the US, no matter if the state permits recreational pot or not. The punishments for a marijuana DUI vary from state to state though. Some state weed DUI laws may treat the offense as a felony with potential jail time, while others view first offenses as a misdemeanor.

In contrast to alcohol, the standard by which pot intoxication is measured to determine a DUI weed charge also varies from state to state. With alcohol, it’s easy. All 50 states have a set blood-alcohol level used to determine intoxication. If a driver has a blood-alcohol level above 0.08 percent, they’re too drunk to drive.

With pot, it’s a little more complicated. THC lingers in a person’s system for a lot longer than alcohol. So, while a blood test may indicate the presence of THC, there’s a very good chance they are in no way intoxicated at that point in time.

Partly for this reason, there is no agreed-upon standard that determines a DUI for weed. Instead, there are three main methods used by states for issuing a marijuana DUI.

1. Impairment DUI

This is the method used by most states. Under this approach, a prosecutor must prove the driver was actually impaired while driving under the influence of weed.

They may do this by highlighting facts surrounding the case, such as erratic driving, the smell of pot, or the presence of weed in the car.

A driver needn’t violate a traffic law in order to face a marijuana impairment DUI. The police may still arrest a driver and charge them with a cannabis DUI if they suspect recent pot use.

2. Per Se DUI

In states with per se pot DUI laws, if a minimum THC concentration is found in a driver’s blood, they may face charges. This is similar to the approach taken with alcohol, but is problematic as it doesn’t necessarily prove impairment. States also have different THC concentration cut-offs, ranging from 2 ng/ml to 5 ng/ml. There are six states with per se pot DUI laws:

  • Colorado
  • Illinois
  • Montana
  • Nevada
  • Ohio
  • Washington

Colorado’s per se weed DUI laws operate slightly differently though. While the other five states take a certain THC blood concentration to be proof of impairment, Colorado only considers it permissible to presume the driver was impaired. This presumption can, however, be challenged by the driver.

3. Zero Tolerance DUI

There are twelve states that consider the presence of any amount of THC in a driver’s blood to be grounds for a pot DUI charge. So, even if you haven’t used cannabis for weeks, you could still have traces of THC in your blood that could result in a marijuana DUI.

Those twelve states are:

  • Arizona
  • Delaware
  • Georgia
  • Indiana
  • Iowa
  • Michigan
  • Oklahoma
  • Pennsylvania
  • Rhode Island
  • South Dakota
  • Utah
  • Wisconsin

Marijuana DUI Laws By State

What is considered ‘driving’ under marijuana DUI laws?

So, states have different approaches towards determining marijuana impairment for drivers, but what constitutes driving?

By law, the driver doesn’t need to actually be driving a vehicle to face a cannabis DUI. All that’s required is that they are “in actual physical control” of the vehicle.

In states with actual impairment DUI laws, a judge presiding over a marijuana DUI case will consider a multitude of factors in assessing whether a driver in a stationary vehicle was nonetheless driving under the influence of pot.

For instance, were the keys in the ignition? Was the engine running? Where was the driver in the vehicle? Was there gas in the tank?

So, even if you think you are being sensible by sleeping off your high at the side of the road, there’s a chance you could still be charged. To avoid this, make sure the engine is off, the keys are stored away, and that you take your rest in the back seat of the car. Oh, and don’t sleep in a place that would suggest you parked there only after driving under the influence of weed.

Marijuana DUI Penalties

Drivers convicted of a pot DUI are likely to face a criminal fine and a suspended license. There could also be jail time in many instances.

Most cannabis DUIs are misdemeanors, though it can rise to a felony offense for repeat infractions or if the facts of the case warrant more extreme sanctions. On rare occasions, a driver could have their license permanently revoked for multiple pot DUIs.

Other potential sanctions include house arrest, probation, community service, participation in victim-impact programs, vehicle seizure, and mandatory substance-abuse treatment.

Most states have maximum penalties in place for cannabis DUIs, and few first-time offenders will face jail time. Subsequent offenses often do carry mandatory minimums though, with sentences increasing with each conviction.

Aggravating factors can also result in a harsher sentence. Such factors may include, the presence of a minor in the car, extremely high blood-THC levels, serious property or bodily damage, and driving without a license.


  1. Ben, Nice article. I am a DWI/DUI Lawyer in Missouri. Handle both Alcohol intoxication and Cannabis/Marijuana impairment cases, and other types of Drug intoxication DUI cases as well.
    MO., is one of the Impairment States. On one pending case, the Lab test simply came back for the presence of THC, with no measurement of ng/ml. Since MO., is not a Per Se State, the measurement would not make or break the case for the State. Impairment must still be shown. The Zero Tolerance States are the worst, as simply testing positive for THC, may mean a possible conviction.
    ONLY handling cases in Missouri; but happy to be of help to anyone in MO., that needs representation.
    Steven Groce, Attorney


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