Marijuana DUI in Iowa

It is a crime in Iowa to operate a motor vehicle while under the influence of alcohol or a drug. Iowa lawyers often refer to the offense as OWI or DUI, but however it is abbreviated, the name of the crime can be deceptive. “Operating” has a broader meaning than “driving,” and “under the influence” does not necessarily require proof that a driver is actually impaired.

The offense of “drugged driving” or “Drug DUI” in Iowa applies when:

  • a driver operates a motor vehicle “under the influence” of a controlled substance, or
  • a driver operates a motor vehicle with a controlled substance in the driver’s blood or urine.

The “controlled substances” to which the law refers include:

  • drugs that are unlawful to possess, and
  • prescription drugs if the driver did not use the drug pursuant to a doctor’s instructions.

Marijuana falls into the first category because Iowa has not yet passed a law that permits the use of medical marijuana.

In addition to a loss of freedom, penalties for a marijuana DUI can have a serious impact on driving privileges, particularly for a second or subsequent offense. They can also lead to a loss of employment for professional drivers, including loss of eligibility for a commercial driver’s license (CDL).

Fortunately, there are several defenses to a marijuana DUI. This is your guide to understanding the offense and how an Iowa DUI lawyer can help if you are charged with the crime.

What Are the Penalties for Marijuana DUI?

In Iowa, a first conviction for a marijuana DUI is a serious misdemeanor. It is punished by:

  • a jail sentence of not less than 48 hours and not more than one year;
  • a fine of $625 to $1,250; and
  • a revocation of driving privileges for 180 days to 1 year.

Some drivers are eligible for a deferred adjudication. If a judge agrees to defer adjudication, the driver is placed on probation and avoids jail time.

A second conviction increases the penalties to:

  • a jail sentence of 7 days to 2 years;
  • a fine of $1,875 to $6,250; and
  • a license revocation of 1 to 2 years.

The penalties for a third conviction are:

  • a jail sentence of 30 days to 5 years;
  • a fine of $3,125 to $9,375; and
  • a license revocation of 6 years.

For all offenses, the court will impose a requirement to participate in substance abuse treatment.

A restricted driver’s license that authorizes work-related driving may be available for at least part of the revocation period. To qualify, the driver must agree to installation of an ignition interlock device on the driver’s vehicle.

What Does “Operating” Mean?

Operating a motor vehicle is a broader term than driving a motor vehicle. People operate a car when they have physical control over the car and the car is moving or its engine is running. Even if the car is not moving, if you are sitting behind the steering wheel with the engine running, you are “operating” the vehicle because the vehicle is under your control.

If you get into a car on a cold night, start the engine to run the heater, and then crawl into the back seat for a nap, you “operated” the car when you started the engine. Whether the police can prove you started the car will depend on the evidence, including admissions you make. For that reason, it is always wise to decline to answer a police officer’s questions until you have a chance to talk to a lawyer.

How Can Prosecutors Prove I Had Marijuana in My Blood or Urine?

The active chemical in marijuana — the chemical that causes a smoker to get high — is THC. In most cases, THC is no longer present in the brain, and no longer capable of having an impact on driving, within a few hours after smoking ceases.

After THC is consumed, it rapidly breaks down and changes into molecules known as metabolites. While metabolites have no impact on the brain, it is much easier to test for metabolites of THC than actual THC. For that reason, testing is usually designed to detect metabolites of THC.

Metabolites of THC are eliminated over time, but they are temporarily stored in the body’s fat. Regular marijuana smokers might have metabolites in their system for days, weeks, or even months after they last smoked.

It doesn’t make much sense to base driving crimes on inactive molecules that have no impact on driving. Many states have therefore required proof of THC, rather than metabolites, in a driver’s blood to prove that the driver committed a crime.

The Iowa Supreme Court has nevertheless concluded that Iowa law prohibits driving with harmless metabolites THC in the driver’s system. That means a driver can be prosecuted for marijuana DUI long after the THC that might impair driving has left the driver’s system.

Are There Any Defenses to a Marijuana DUI Charge?

An experienced Iowa marijuana DUI lawyer will explore every avenue to the defense of a marijuana DUI charge. The defense must be tailored to the facts of the case. In some cases, for example, whether the driver “operated” the vehicle will be a contested fact.

In many cases, the defense focuses on whether the police had a legal justification for stopping the driver. The police are not permitted to stop drivers on a mere hunch that they are doing something wrong, but must have a reason to believe they have violated the law.

A lawyer may also challenge a driver’s arrest as unsupported by probable cause. When a driver does well on field sobriety tests and passes a portable breath test, an officer may not have any justification to arrest the driver. The police might also have failed to follow required procedures, such as obtaining consent or a search warrant, before taking a sample of the driver’s blood.

The reliability of test results can be challenged in appropriate circumstances. Although the law is not yet clear, a driver who consumed medical marijuana in a state that authorized the use of marijuana might have a justification for driving in Iowa day later while THC metabolites were still in his or her system.

Defending a marijuana DUI charge in Iowa requires ingenuity, determination, and a careful assessment of the facts and law. At worst, raising a defense will almost always put a driver in a better position to negotiate a favorable outcome.

You can read our other blogs about OWI for Commercial Vehicles, how DUI affect employment background checks or DUI expungement.  

This is not legal advice.

Call our office to discuss your case.



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