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Health and Safety Code 11550 – Use or Under the Influence of a Controlled Substance

11550. (a) No person shall use, or be under the influence of any controlled substance which is (1) specified in subdivision (b), (c), or (e), or paragraph (1) of subdivision (f) of Section 11054, specified in paragraph (14), (15), (21), (22), or (23) of subdivision (d) of Section 11054, specified in subdivision (b) or (c) of Section 11055, or specified in paragraph (1) or (2) of subdivision (d) or in paragraph (3) of subdivision (e) of Section 11055, or (2) a narcotic drug classified in Schedule III, IV, or V, except when administered by or under the direction of a person licensed by the state to dispense, prescribe, or administer controlled substances. It shall be the burden of the defense to show that it comes within the exception. Any person convicted of violating this subdivision is guilty of a misdemeanor and shall be sentenced to serve a term of not less than 90 days or more than one year in a county jail. The court may place a person convicted under this subdivision on probation for a period not to exceed five years and, except as provided in subdivision (c), shall in all cases in which probation is granted require, as a condition thereof, that the person be confined in a county jail for at least 90 days. Other than as provided by subdivision (c), in no event shall the court have the power to absolve a person who violates this subdivision from the obligation of spending at least 90 days in confinement in a county jail.

Under this law, it is illegal to be under the influence of a controlled substance. This offense is charged as a misdemeanor. If one is found guilty, they may qualify for drug diversion pursuant to California Penal Code 1000. They may also qualify for a diversion program under Proposition 36.

Potential Sentence: At least 90 days in the county jail, but possibly up to one year.

To find a defendant guilty, the prosecutors must meet their burden of proving these elements beyond a reasonable doubt:


  1. Willful and illegal use of a controlled substance by the defendant shortly before the arrest. (Relevant to an allegation that defendant “used” a controlled substance. OR….
  2. The defendant was illegally under the influence of a controlled substance as a result of his or her will to do so at the time of the arrest. (This is relevant to being under the influence of a controlled substance).

Explanation of the Law:

  • The term “willful” means that the person did the act on purpose, i.e. had the intent to “get high.” People v. Little (2004) 115 Cal.App.4th 766. Penal Code 7, subsection (1) defines willfully as “simply a purpose or willingness to commit the act, or make the omission referred to. It does not require any intent to violate law, or to injure another, or to acquire any advantage.”
  • Theory One: “Use” is defined as immediate use prior to arrest, or current use at time of arrest. (People v. Jones (1987) 189 Cal.App.3d 398.) The People v. Jones case established that use of drugs 48 hours prior to arrest was enough to support the offense.
  • Theory Two: Being under the influence of a controlled substance means that someone has consumed an illegal drug and the drug has induced a narcotic effect on the user affecting the functioning of the brain, nervous system, or other normal function of the body. This change in the body may also be found if it creates a noticeable defect in mental or physical abilities.
  • Additionally, under either of these theories, the specific substance must be identified and included in the allegation. Sallas v. Municipal Court (1978) 86 Cal.App.3d 737.


  • Valid Prescription: A defendant will not be guilty under this section if he or she had a legal prescription from a health care professional authorized to prescribe such a drug. Authorized individuals include a physician, dentist, podiatrist, or even a veterinarian. A naturopathic doctor is also allowed to provide a valid prescription for the purposes of this defense. All these professionals must be licensed in California for the defense to be valid. If the prosecution is not able to prove that the defendant did not have a valid prescription, an acquittal is in order.
  • No use or state of being under the influence: If you did not actually use a drug or were not under the influence of a controlled substance, then obviously you cannot be found guilty of the offense. If there is no physical evidence (i.e. drug tests or other samples) that confirm you were under the influence, the prosecution won't have a case against you.
  • Involuntary Intoxication: If you did not consume a drug by an act of your own free will, then the prosecution will be unable to prove the “willfully” component of the elements. Although it seems like it would be a likely excuse for an offense under this section, this defense does have merit in situations where someone was drugged by another without their knowledge.

Legal Resources: 

Redding Auto Accident Attorney

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