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Testing for Drivers Under the Influence of Marijuana

Discover How Policemen Deal With High Driving As Marijuana Became Legalized In California

Voters in the state of California approved the use and cultivation of recreational marijuana by passing Proposition 64 in November of 2016. Since then, policemen have faced challenging roles due to the possibility of increased road incidents involving drivers under the influence of some type of drug. So, how do policemen determine if a driver is under the influence of marijuana when he or she is stopped on the road? We will look at some of the tests that lawmakers recommended to detect levels of THC, an active ingredient found in marijuana among drivers.

Field sobriety test

If a California policeman decides to pull over a driver suspected to be under the influence of marijuana, the initial test that can be conducted is the field sobriety test. The field sobriety test consists of a number of physical and mental exercises that the attending police officer can perform while undergoing a marijuana DUI investigation. This test is often relied on when determining whether or not to arrest a person who is suspected to be driving under the influence. The tests that are performed as part of a field sobriety test include the:

  • Horizontal Gaze Nystagmus Test

This test is administered by a police officer. The officer will move an object or his or her finger from side to side in front of the driver’s face. The goal of the Horizontal Gaze Nystagmus is to detect an involuntary movement of they eye resulting directly from a high level of of intoxication. Under normal circumstances, the eye of the person being administered the test will move naturally after being strained beyond a forty-five degree angle. However, if the person’s eye begins to move at or before a forty-five degree angle, police officers in the State of California can use this reaction as evidence against the driver and validate the suspicion of being “high” while driving.

  • Walk and Turn Test

Another test that can be administered to a suspected high driver is the “Walk and Turn Test”. This test is also often referred to as the “Walk the line test”. When using this test, the on-duty police officer will provide clear instructions to the suspected driver and make a careful observation of the following:

  • Inability to maintain balance while walking
  • Incorrect number of steps completed
  • Struggle to stay on the line
  • Breaks while walking
  • Starting prior to instruction by the officer
  • One Leg Stand Test

The “One Leg Stand” may also be conducted by the police officer. When administering this test, the suspect is given instruction to raise his or her foot, then, hold still and look down. While the suspect is carrying out this task, the officer will observe the presence of the following behaviors:

  • Hopping
  • Swaying
  • Putting foot down

According to the NHTSA, this test is proven effective 65% of the time.

Blood, Breath and/or Urine Test

Under California law, if a police officer has a valid reason to pull over a driver that he or she suspects to be under the influence of marijuana, the person may be asked to give a blood sample, urine sample, or undergo breath analysis. A urine sample isn’t typically used when testing for drivers suspected to be under the influence of marijuana. However, if the police officer is unable to get blood or breath analysis, the urine test may be required.

Saliva Drug Swab Test

Another test currently being administered by some police officers in California, is a saliva drug swab test. This test uses a mouth swab device to confirm the existence of marijuana and other drugs in impaired drivers. These drug test machines retail for roughly $6,000 per unit and are currently being used in dozens of states across the country.

To use the machine, the operator of the vehicle is instructed to run the mouth swab around the inside of his or her mouth for up to four minutes. The results of the test take approximately 8 minutes to give a result. Ideally, the result of the test should verify the presence of THC or other drugs like meth, cocaine or methadone. Much like tests that screen for alcohol, drivers cannot be forced to submit to a saliva drug swab test.

There is still great concern about the accuracy of the tests performed on drivers who are suspected to be under the influence of marijuana or other drugs. Traces of THC can remain in a person’s system for several days, unlike alcohol. Because of this, people in a courtroom may have apprehensions regarding whether a particular driver was under the influence of marijuana at the time the sobriety tests were administered. Moreover, under California law, there is no legal threshold regarding the amount of drugs in a person’s system when it comes to driving an automobile.

Other ways to check if a driver is high on drugs

Police officers are given extensive training in order to educate them about the symptoms associated with drug intoxication. They are instructed to look for bloodshot eyes, the smell of marijuana, as well as unusual driving habits while on the road.

According to the National Conference of State Legislatures, “Scientific data indicate the potential therapeutic value of cannabinoid drugs, primarily THC, for pain relief, control of nausea and vomiting, and appetite stimulation; smoked marijuana, however, is a crude THC delivery system that also delivers harmful substances. The psychological effects of cannabinoids, such as anxiety reduction, sedation, and euphoria can influence their potential therapeutic value. Those effects are potentially undesirable for certain patients and situations and beneficial for others. In addition, psychological effects can complicate the interpretation of other aspects of the drug’s effect.” The use of medical marijuana increases the difficulty for police officers to keep our roads safe. This is an issue that lawmakers in many states will have to face going forward.

Speak with a Personal Injury Attorney in Carlsbad, CA if You Have Been in an Accident Involving a Driver Under the Influence of any Drug

At Stipp Law Firm, APC, we have a long track record of defending victims of car accidents in Carlsbad. We will do everything to make sure that you know what your rights are and that you are compensated for your injuries. Contact us today for a free consultation at 760-994-0480.