8 Best Defenses for an Arizona Marijuana DUI Charge

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After a person is charged with a Marijuana DUI in Arizona either under ARS § 28-1381(A)(1) or a per se charge under ARS § 28-1381(A)(3), they may wonder which defenses an attorney can use to shield a client from liability.

Fortunately, various laws and constitutional provisions protect individuals charged with an offense, and law enforcement must follow procedures to obtain evidence properly and charge a defendant. Several defenses are often used in a Marijuana DUI charge in Arizona.

1. Illegal Vehicle Searches

The Constitution of the United States and the Constitution of Arizona provide individuals accused of crimes with several rights and protections. Perhaps most importantly, constitutional law protects individuals from improper searches and seizures.

In general, police need to obtain a search warrant to search and seize evidence located inside homes, containers, and other locations.

In some situations, police may effectuate a search without a warrant if they can demonstrate that an emergency or other circumstance existed such that they could not obtain a search warrant. After the police place someone under arrest, they can also search that person even if they did not get a search warrant.

Sometimes, police may conduct a search even though they do not have the authority to perform the search.

If a court rules that a vehicle search was improper, then any evidence that is obtained because of that search may be subject to the following restrictions:

  • Excluded as evidence at trial.
  • Admitted in part and excluded in part.
  • Admitted with explanatory instructions to the jury.


If the prosecution cannot make a case against a defendant without using the suppressed evidence, it is possible that a criminal case will be dismissed, and this is a common occurrence with a Marijuana DUI case in Arizona.

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2. Improper Police Stops Resulting in Marijuana DUI Charge

Police also need to show that they believed that criminal activity was afoot before they conduct a stop of people in public places. This is called reasonable suspicion.  Sometimes, police will stop individuals randomly or stop people without proper justification.

If a stop was conducted illegally, then any evidence that was seized during the stop may be suppressed at trial and cannot be used against a criminal defendant. 

As a result, arguing that a stop was improper is a powerful tool when defending a Marijuana DUI in Arizona. An experienced criminal defense attorney can ensure that evidence seized due to an improper stop is excluded at trial.

3. Faulty Sobriety Testing Equipment

Police often perform various tests during a Marijuana DUI case in Arizona. For instance, when proving that an individual was intoxicated while they operated a vehicle, police may sample the breath or alcohol of a defendant. Moreover, when proving that an individual was in possession of drugs or other illicit substances, they may wish to test the substances to determine the composition of the substances. 

However, testing equipment must be properly calibrated to perform a test accurately. Moreover, numerous testing devices need to be certified on a regular basis to ensure that the equipment is currently able to accurately perform tests.

If authorities use faulty equipment or fail to obtain the proper certification for the testing equipment, the test results may be suppressed, and defendants may be able to avoid prosecution.

4. Chain of Custody for Handling Evidence

When performing tests in a Marijuana DUI case in Arizona, it is important that police maintain the chain of custody. Chain of custody means that the police can account for all the people who interacted with a piece of evidence from the time it was collected until the time it was tested by professionals. 

If police cannot show that evidence was properly handled from the time it was collected to the time it was tested, it is possible that contaminants or other issues may have been introduced into the evidence, interfering with the proper testing of the evidence.

In severe cases, evidence that was not subject to a proper chain of custody may be suppressed, which can be fatal to a prosecutor’s case against a criminal defendant.

5. Improper Police Action to Obtain Statements

Police officers need to be cautious when taking statements from individuals, and the failure to abide by these protections may be a defense in a Marijuana DUI case in Arizona. As many people know from movies and television shows, police need to inform individuals that they have the right to remain silent and have the right to an attorney before they subject someone to custodial interrogation.

Custodial interrogation is generally defined as a situation in which an individual feels like they are in custody by the authorities.

Individuals should immediately request an attorney whenever they are questioned by police. An attorney can ensure that someone does not face the authorities alone and can explain the legal consequences of different strategies.

Moreover, individuals should remain silent whenever they are questioned by police until their attorney arrives at the scene. Individuals may not have the right to be read their rights in a variety of situations, so it is important to remain silent whenever there is any question about whether an individual should speak to the police.

If police officers do not respect the rights of criminal defendants, any statement made by the individual may be suppressed at a later time. Moreover, any evidence that is seized because of such a statement may also be suppressed.

As a result, the failure to properly read a defendant his or her rights or the failure to abide by a defendant’s wishes is a powerful defense in a Marijuana DUI case in Arizona.

6. Defective or Illegal Search Warrants

Another common defense with a Marijuana DUI in Arizona is defective warrants. A search warrant needs to particularly describe the place to be searched and the items to be seized.

If the search warrant is not particular enough, it may be defective, and this could create a strong defense in a criminal case.

Moreover, police cannot exceed the scope of the warrant when performing the search. For instance, police are not able to continue searching a home once they discover the item for which they are searching. In addition, police can also generally only observe items in their plain view and are unable to pick up and inspect items without further justification.

Furthermore, police may need to knock before executing a search warrant, and the failure to do so can also be fatal to the search. It is important to work with an experienced criminal defense lawyer who knows all of the ways that a warrant may be defective so that criminal defendants have the best chance at advancing a defense.

7. Lack of Impairment – Beyond Reasonable Doubt

Lack of impairment can also be an important defense in a Marijuana DUI case. Police often need to prove that an individual was impaired to charge them with a DUI. This makes sense because the impairment itself is what could constitute a public danger because impaired drivers might not be able to properly operate a vehicle and may cause an accident.

However, some people might not be impaired, even if they consume marijuana. For instance, individuals may have a tolerance to marijuana because they have used marijuana for a long period of time, and accordingly, marijuana does not have a substantial impact on the person.

Of course, lack of impairment only works as a defense in certain situations, and this may not be a defense for all people who face Marijuana DUI cases. However, this defense can be a powerful tool when defending against criminal charges related to marijuana use.

8. Lack of Vehicle Operation – No Actual Physical Control

It is important to note that individuals usually need to be actively operating a vehicle, or the technical term “in actual physical control,” to be charged with a Marijuana DUI. This often involves the car being turned on and the driver being actively involved in the operation of the vehicle. As a result, a passenger in a car will ordinarily not be liable for a Marijuana DUI even though they are inside a vehicle while intoxicated because someone else operated a vehicle.

If a driver is behind the wheel of a vehicle, but the car is turned off and parked, they ordinarily cannot be charged with a Marijuana DUI.

Moreover, if an individual is merely walking to a vehicle, they may not be charged with a Marijuana DUI even if they intend to get inside the vehicle and operate the vehicle.

As a result, the range of situations in which an individual can be charged with a Marijuana DUI is somewhat limited. A skilled criminal defense attorney should know if your circumstances exclude you from being prosecuted for a Marijuana DUI.

All told, there are many defenses that can be raised in a Marijuana DUI case in Arizona. It is important to speak with an experienced criminal defense attorney at Gurion Legal to ensure that every viable defense that can be raised in a case is being raised so that you can best protect your rights.

Give our firm a call immediately so we can evaluate your case from top to bottom and structure the best winning case scenario possible. Call (480) 800-0020 to speak with our legal team.