Driving Under the Influence of Drugs (DUI Drugs)

Driving under the influence of any drug is a crime often referred to as drugged driving, DUID or "driving stoned”. Section 23152(f) of the Vehicle Code provides that the crime has essentially the same legal effect as driving under the influence of alcohol:

  • It is unlawful for a person who is under the influence of any drug to drive a vehicle.
  • It is unlawful for a person who is under the combined influence of any alcoholic beverage and drug to drive a vehicle.

Whether a prescription medication, marijuana, or an illegal drug controlled, California law does not actually prohibit a certain amount of a given drug in a person’s system. The law simply prohibits a person from “driving under the influence” of a drug: it must affect a driver so that their mental or physical abilities are so impaired that he or she is no longer able to drive a vehicle with the caution of a sober person, using ordinary care, under similar circumstances — the same definition as for driving under the influence of alcohol.

Also, there are differences when administering chemical testing for DUI drugs and DUI marijuana. There is a standard breath test administered when testing a DUI alcohol suspect. A breath test will not show the presence of marijuana or drugs. Therefore, testing for drugs must be administered by blood test. Expert (DRE) is may be called into the case when drugs are involved to examine the individual in question. A DRE can testify to the symptoms of drugs or marijuana and influence of drugs or marijuana.

There are also a few differences between DUI drugs and DUI marijuana in how the chemical testing is administered. Where the standard test given to DUI suspects is the breath test, a breath test will not register the presence of marijuana or drugs. Therefore, if the officer suspects the individual was driving under the influence of marijuana or drugs, a blood test will be administered.

Note:  A driver can be using marijuana or prescription drugs legally, but just as with the legal use of alcohol, they can be charged with driving under the influence if they are impaired.” See ‘‘How Legal Drug Use Can Lead to a DUI or DWI’’.

There are several studies being conducted by scientists to further research the effects of driving under the influence of drugs. More research needs to be conducted to determine the following:

  1. Determine the degree of impairment (if any) of the quantity of drugs consumed.
  2. Determine the active life of the drugs in the blood
  3. Identify individual tolerance to drugs.

For more information on the effects of marijuana on driving, visit the firm’s materials on DUI Marijuana and DUI Drugs.

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