How Do Police Officers Confirm a Marijuana DUI?

There has been a rise in the frequency of DUI charges involving marijuana usage since the US eased its laws against its possession and use. 

If the police have reason to believe that you are under the influence of marijuana, they can arrest you. You should consult reputed attorneys in your area if you have been charged with marijuana DUI, as they will have the necessary experience and skills to handle your case.

Rather than depending solely on the findings of chemical testing, the police and prosecutor must substantiate their claims that the driver was under the influence of marijuana. This article will look at how police officers confirm a marijuana DUI.

Physical Test

Cannabis and other narcotics, both legal and illicit, can impair one’s ability to drive, according to California Vehicle Code Section 23152(f) VC. Before the police can carry out the chemical tests, they can do the physical tests, as they have the necessary training and know what to look for. Some of the things they look for include:

  • Red or dilated pupils
  • Rapid heart rate or fast breathing
  • Marijuana smell
  • Driving conduct: running red lights and stop signs 

The police and the DRE (Drug Recognition Expert) officer can subject the accused to a field sobriety test (FST). This, however, has several drawbacks, such as: 

  • The police cannot force you to take the test if you are over 21 
  • Taking the test is unnecessary, especially if you are not on DUI probation
  • An officer cannot force you to take the test if they have not legally arrested you

If you fail an FST test, the police can take it as evidence of a marijuana DUI.

Chemical Test

The chemical tests that police officers can subject suspects of marijuana DUI include tests of:

  • Urine
  • Saliva
  • Blood

Unlike alcohol, marijuana does not gradually disappear from an individual’s body. Because of this, the chemical tests will have several downsides, such as:

  • The test cannot tell the amount of marijuana the driver used
  • It will be impossible to know the last time the driver consumed marijuana

Saliva and Blood Tests

Saliva and blood tests are exclusively for identifying the presence of THC (delta-9-tetrahydrocannabinol) within the body’s systems of a motorist. Tetrahydrocannabinol (THC) is a psychotropic compound that is present in the cannabis plant. 

The presence of any quantity of THC in a driver’s bloodstream may lead to charges of driving under the influence (DUI).

The most prevalent chemical test for DUI cases involving marijuana is a blood test. However, the initial examination frequently includes the administration of saliva testing. These tests are sensitive to recent marijuana use but cannot quantify the dosage.

High angle shot of a female rolling a joint
Image source

Urine Tests

In the US, urine tests are not as common as saliva and blood tests. Nonetheless, in certain circumstances, a police officer might ask that you finish these evaluations. THC is also undetectable in urine tests. Urine tests can detect inert metabolites of marijuana use.

If the tests show the presence of marijuana, the prosecution will do its best to ensure that the court convicts you of marijuana DUI. For this reason, you should seek the services of qualified defense attorneys. The attorney will: 

  • Dispute that the motorist has not been using marijuana.
  • Argue that the motorist was not impaired.
  • Disagree with the chemical test results.
  • Try to prove that the traffic stop that led to the arrest of the driver was illegal.
  • Come up with evidence explaining the driver’s behavior, like distractions and medical conditions. 

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Driving under the influence of marijuana is illegal, and the court will sentence anyone found guilty. That’s why it is best to look for the best advocate. If you find yourself in such a case, consult a defense attorney.