A marijuana DUI means due to the consumption of marijuana, the driver’s ability to operate a motor vehicle was significantly and materially affected to the degree that they could no longer operate a motor vehicle safely.

There are a couple of very important parts to this definition that must be considered.

First, the driving must have been materially and substantially affected.

This is a high level of evidence.

Crossing over a lane marker a couple times, which isn’t unreasonable (and could also be another reason like distracted driving, which can be a defense), isn’t material and substantial.

If, because of the marijuana, a person was driving in a manner that was dangerous, perhaps almost striking other vehicles, all over the road, running red lights and clearly intoxicated; it can be said that their driving was materially and substantially affected.

The other consideration is that the driver could no longer drive in a safe and normal manner.

This means that a person can be under the influence of marijuana, but as long as they were able to drive safely, then their driving isn’t unlawful.

There are persons who have built up a tolerance to marijuana to the degree that they could drive safely even immediately after consumption.

This is definitely not recommended for anyone, no matter their tolerance.

Nevertheless, the law requires that to be unlawful, their ability to drive has been altered to the degree that they could no longer drive in a safe and normal manner.

However, the video may show that the light was yellow, a turn signal was used, or “swerving” was minor and within your own lane.

Knowing how to properly review a dash-cam video is the key to for your case to be dismissed early on.

Often times, the best evidence is the observation of the actual driving.

This is frequently captured on the police car dash recording device.

It will also be described by the officer, if witnessed, in the police report.

Police and prosecutors will also seek to use the results of standardized field sobriety tests.

These tests are the walk-and-turn, one-leg stand and horizontal gaze nystagmus (HGN) all of which were designed and validated for detection of alcohol impairment, not marijuana.

Despite the fact that they were created for alcohol, the inability to walk a straight line without losing your balance, which is tested during the walk-and-turn test, may still be helpful in determining a person’s ability to balance, not necessarily drive.

The question becomes this; to what degree does that ability translates to the ability to drive while under the influence of marijuana?

There are non-standardized tests that may be more applicable to marijuana.

For instance, there have been studies that conclude that the Lack of Convergence test and the Modified Romberg test are better at identifying a person who is under the influence of marijuana.

Again, just because someone may be “high” on marijuana doesn’t automatically mean their ability to drive has been “significantly and materially” affected by the marijuana to the degree they’re no longer able to drive in a normal and safe manner.

There are many strategies to be employed for a marijuana DUI, but it’s very important that the defense lawyer knows:

• the scientific principles of THC specific absorption and elimination (as well as tolerance),
• cannabis specific field sobriety testing, and a
• solid understanding of Michigan law.

It can get very complicated.

There are several different statutory laws, which must also be interpreted with Michigan case law in order to develop the proper strategy.

It’s also important to be able to understand the chemical test and the relationship between active THC and THC-COOH metabolite.

If a drug recognition expert was used to perform the investigation, a lawyer is familiar with that protocol.

The attorney must also have taken the course to create a successful defense.

In general, it’s necessary to evaluate the driving evidence.

It’s also necessary to determine whether the field sobriety tests were administered and evaluated properly, and to determine the officer’s training for investigating drug cases.

Then, a proper evaluation of the blood test, applying the correct measurement calculations, and performing an analysis of the data that supports the chemical test to determine if it’s valid and reliable.

Only an expert in forensic science, particularly an ACS Forensic Lawyer-Scientist, would be ideal.

Low levels of THC in blood aren’t a very reliable indicator of intoxication or inability to drive, especially when there’s such a high margin of uncertainty (29%).

Higher levels of THC can be indicative of a direct relationship of intoxication but they are still very dependent upon the individual user with respect to their tolerance, along with the recency of use and route of administration.

There are different absorption and peak intoxication levels depending upon whether the marijuana was smoked, vaped or eaten.

In summary, the blood test may be helpful in some cases but in many cases, it isn’t.

There are several different statutory laws which must also be interpreted with Michigan case law in order to develop the proper strategy.

It’s also important to be able to understand the chemical test and the relationship between active THC and THC-COOH metabolite.

If a drug recognition expert was used to perform the investigation, a lawyer is familiar with that protocol and has also taken the course is necessary to create a successful defense.

In general, it’s necessary to evaluate the driving evidence.

It’s also necessary to determine whether the field sobriety tests were administered and evaluated properly, and to determine the officer’s training for investigating drug cases.

Then, a proper evaluation of the blood test, applying the correct measurement calculations, and performing an analysis of the data that supports the chemical test to determine if it’s valid and reliable.

Only an expert in forensic science, in particular an ACS Forensic Lawyer-Scientist, would be ideal.

The penalty for a first offense OWI by marijuana is probation of up to two years.

Jail is usually not a consideration unless there were aggravating circumstances like an accident, injury or reckless disregard for persons or property.

There are some judges who jail first offenders, but they are very rare.

OWI – first offense is punishable by up to 93 days in jail so if there’s a probation violation, jail time is very possible.

An OWI conviction is six points, while Operating While Visibly Intoxicated (OWVI) is four points added to a driving record.

Alcohol/drug abstinence and random testing is very common. Sometimes, a good argument can be made to eliminate the alcohol testing.

However, this is highly dependent upon the judge.

Studies have shown that the peak acute effects following cannabis inhalation are typically obtained within 10 to 30 minutes, with most effects dissipating after one hour.

Depending upon the person, impairment from cannabis will clear up three to four hours after use.

This time span could be recommended to users as a minimum wait period before driving. (Fischer et al., 2011 Lower risk cannabis use guidelines for Canada).

The Michigan Impaired Driving Safety Commission performed a very thorough study on whether a THC contraction, like 5 ng/ml of blood, would equate to intoxication similar to .08 g/210 of breath or 100 ml of blood alcohol.