DRUG CRIMES LAW — CALIFORNIA
Being Under the Influence of Drugs in California — HS §11550
Reviewed by Daniel S. Rubin, CA Bar 302093 · Los Angeles Criminal Defense Attorney
Quick Reference
Under the Influence of Drugs California — At a Glance
- Law / Code
- HS §11550
- Classification
- Misdemeanor
- Maximum Penalty
- Up to 1 year county jail
- Probation Eligible
- Yes
- Strike Offense
- No
- Related Codes
- HS §11350PC §647(f)PC §1000
What Is Under the Influence of Drugs California Under California Law?
Legal Framework. Health and Safety Code § 11550(a) makes it a crime to be under the influence of a controlled substance, or certain specified controlled-substance analogs, unless the person is using the drug under the direction of a person licensed to dispense, prescribe, administer, or furnish it. The prosecution must prove actual influence: that the defendant’s physical or mental functioning was impaired in a detectable manner by a qualifying drug. Mere past use, drug possession, addiction, unusual behavior, or the presence of drug metabolites does not alone establish the offense. California cases commonly describe the required condition as symptoms showing the person had used a controlled substance recently enough to be presently under its influence, with impaired nervous-system functioning or behavior consistent with that use.
The Prosecution's Burden. A violation of HS § 11550(a) is generally a misdemeanor, not a wobbler. The ordinary sentencing provision permits confinement in county jail for up to one year, but Proposition 47 added HS § 11550(e), which generally directs courts to impose a diversion and treatment-based disposition for eligible defendants rather than incarceration. Eligibility and the available program depend on the person’s record, current allegations, and statutory exclusions. The statute also authorizes certain limited detention and examination procedures in HS § 11550(b), including examination by qualified personnel in specified circumstances. A charge may begin after LAPD or LASD officers report observed symptoms and a drug-recognition evaluation, but police observations remain evidence to test—not a substitute for proof beyond a reasonable doubt.
Potential Consequences. HS § 11550 is a status-and-condition offense, distinct from drug possession, drug sales, and drug-impaired driving. Possession charges require proof that a person exercised control over a substance and knew of its presence and nature; being under the influence does not require officers to recover drugs. Conversely, a person can possess a prescription medication without violating HS § 11550 if it is used as directed, and can be impaired by a substance that does not fall within the statute without committing this particular offense. When alleged driving is involved, prosecutors often charge Vehicle Code § 23152(f), driving under the influence of drugs, or VC § 23152(g), driving under the combined influence of alcohol and drugs, because those offenses require proof of driving as well as impairment.
02 — Elements of the Crime
Elements the Prosecution Must Prove Under HS §11550
To convict under HS §11550, the prosecution must prove each of the following elements beyond a reasonable doubt:
Under the Influence at the Time of Arrest
The defendant was actually experiencing the psychopharmacological effects of a controlled substance at the time of arrest.
Willful Use
The substance was used voluntarily — involuntary intoxication is a complete defense.
Identified as a Controlled Substance
The substance must be a listed controlled substance under the Uniform Controlled Substances Act.
All elements must be proven beyond a reasonable doubt.
Penalties
Penalties for Under the Influence of Drugs California in California
Misdemeanor
Up to 1 year in county jail, mandatory treatment as a condition of probation, and PC §1000 diversion available in the vast majority of first-time cases.
Additional Consequences
- Often filed with HS §11350 or HS §11364 companion charges
- Prop 36 residential-treatment option in aggravated cases
- PC §1001.36 mental-health diversion for underlying disorders
05 — Defense Strategies
How Rubin Law Defends Under the Influence of Drugs California Charges
Rubin Law, P.C. attacks the elements of HS §11550 and drives outcomes that avoid conviction where possible.
No Proof of Present Influence
The central issue in an HS § 11550 case is whether the person was actually under the influence at the charged time. The prosecution cannot establish that element merely by showing a prior history of use, possession of paraphernalia, an admission of earlier use, or a positive chemical test. Many substances leave metabolites detectable after their impairing effects have ended. Defense work focuses on the timing of the alleged use, video, dispatch and body-camera timelines, witness observations, and the specific symptoms officers documented. If the evidence shows only residual metabolites or speculation about recent use, the statutory element of present influence is not proved.
U.S. Const. amend. IV
Challenge the Drug-Recognition Opinion
HS § 11550 prosecutions often depend heavily on an officer’s claim that observed signs matched a particular drug category. Those opinions can be undermined where the officer lacked sufficient training, failed to conduct a complete evaluation, relied on vague or leading questions, or did not account for contradictory observations. Pupils, pulse, speech, balance, skin appearance, and behavior are not drug-specific findings. The defense can examine the officer’s training records, the evaluation protocol, contemporaneous reports, body-worn camera footage, and any differences between notes and testimony. A confident conclusion unsupported by reliable observations is not proof beyond a reasonable doubt.
17 CCR §1219.3
Medical Conditions and Innocent Explanations
Symptoms commonly cited in HS § 11550 arrests—unsteady gait, tremors, fatigue, rapid or slow pulse, anxiety, confusion, or abnormal pupils—can result from medical conditions, injury, exhaustion, dehydration, panic, diabetes, neurological disorders, or ordinary prescribed medication use. A defense investigation obtains relevant medical records when appropriate, identifies baseline conditions, and compares them with the observations alleged by law enforcement. The point is not that every symptom must have a medical cause; it is that the prosecution must exclude reasonable doubt that the symptoms reflected unlawful current drug influence. Objective medical evidence can materially change charging and negotiation decisions.
NHTSA SFST
Lawful Prescription Use
HS § 11550(a) expressly excludes a person who is under the direction of a licensed person authorized to dispense, prescribe, administer, or furnish the substance. A valid prescription alone is not always the end of the inquiry; the defense must establish that the medication was used as directed and that the statutory exception applies to the facts. Pharmacy records, prescription labels, physician documentation, dosage instructions, and timing evidence may be critical. This defense is particularly important where officers assume that impairment-like symptoms prove illicit use without investigating whether the person was following a legitimate treatment plan.
VC §23152
Suppress an Unlawful Detention or Search
An officer needs a lawful basis to detain a person, and a search generally requires a warrant or a recognized exception. In an HS § 11550 case, the initial contact may be challenged when police acted on a bare hunch, prolonged a consensual encounter without reasonable suspicion, searched pockets or a vehicle without legal justification, or obtained statements after an unlawful arrest. Evidence discovered through a Fourth Amendment violation may be excluded under Penal Code § 1538.5. Suppression can remove drugs, admissions, observations made after an illegal detention, or other evidence the prosecution needs to prove current influence.
17 CCR §1219.1
Seek Statutory Diversion or a Noncriminal Resolution
Where evidence creates litigation risk but treatment is appropriate, the defense evaluates HS § 11550(e) diversion and other available statutory or local alternatives. The legal question is not simply whether a person would benefit from services; it is whether the charged offense, prior history, eligibility rules, and court procedures permit a disposition that avoids a conviction. In Los Angeles County, counsel can present treatment records, a verified prescription history, negative follow-up testing, and a concrete plan to the City Attorney or District Attorney when seeking a reduction, dismissal pathway, or diversion placement. Early, documented compliance is often more persuasive than unsupported promises.
VC §23103.5
Constitutional Sources: Fourth Amendment — U.S. Constitution
Collateral Consequences of a Under the Influence of Drugs California Conviction
A conviction does not end when the jail sentence does. These are the long-tail consequences that shape how we negotiate and litigate every case.
Immigration Consequences
A conviction can trigger removal, inadmissibility, or denial of naturalization for non-citizens. Even a plea to a reduced charge may be treated as a conviction under federal immigration law. We build every plea with the immigration file in mind.
Professional Licensing
Nurses, teachers, contractors, real estate agents, CDL holders, and lawyers must self-report criminal convictions to their licensing boards. Boards can suspend, restrict, or revoke a license based on the underlying conduct — not just the conviction.
Employment & Background Checks
A conviction shows up on virtually every background check for the rest of your life absent expungement under PC §1203.4 or record sealing. Employers in healthcare, finance, government, and childcare treat it as disqualifying.
Housing Applications
Private landlords, subsidized housing programs, and student housing all screen criminal records. A recent conviction can end an application before it is reviewed. We negotiate with the record in mind.
Questions
Frequently Asked — Under the Influence of Drugs California
What must the prosecutor prove under HS § 11550?
For a conviction under Health and Safety Code § 11550(a), the prosecutor must prove that you were under the influence of a controlled substance or a qualifying controlled-substance analog at the relevant time, and that your use was not under the direction of a licensed person authorized to prescribe, dispense, administer, or furnish it. The issue is present influence, not simply whether you have ever used drugs or whether a test detects metabolites. The prosecution generally relies on officer observations, statements, a drug-recognition evaluation, and sometimes chemical testing. A test result may support the case, but it does not by itself establish when the drug was used or whether it was causing current impairment.
Is being under the influence of drugs a felony in California?
Ordinarily, no. A violation of HS § 11550(a) is a misdemeanor, not a felony or a wobbler. The statute’s general penalty language permits up to one year in county jail, but HS § 11550(e), added through Proposition 47, generally provides a diversion and treatment-oriented framework for eligible defendants. The actual outcome can depend on eligibility, criminal history, alleged conduct, probation status, and whether the case includes other charges. A person can still face more serious exposure when the same incident involves possession for sale, weapons allegations, violations of probation or parole, resisting an officer, or driving under the influence. Those are separate offenses with separate elements and consequences.
Can police arrest me for HS § 11550 without finding drugs on me?
Yes. HS § 11550 does not require proof that drugs were found in your pocket, vehicle, or home. The offense concerns being under the influence at the time alleged, so officers may make an arrest based on claimed physical symptoms, behavior, admissions, and a trained officer’s assessment. But the absence of drugs can be important in the defense because it may expose gaps in the prosecution’s timeline and conclusion. Police still need probable cause for an arrest, and the prosecutor must later prove the charge beyond a reasonable doubt. A vague claim that someone looked impaired is not automatically sufficient proof of unlawful drug influence.
Will a positive drug test prove I was under the influence?
Not necessarily. A positive blood or urine result can show that a substance or metabolite was present, but it does not automatically prove current influence under HS § 11550. Detection windows vary greatly by substance, frequency of use, body chemistry, and test type. Some tests identify inactive metabolites that remain after impairing effects have passed. The prosecution must connect the result to actual influence at the charged time, usually through observations and expert or officer testimony. The defense can examine the collection timeline, laboratory procedures, chain of custody, cutoff levels, whether the test identifies an active compound or metabolite, and whether medical or innocent explanations better account for the alleged symptoms.
Does a valid prescription protect me from an HS § 11550 charge?
It can. HS § 11550(a) does not apply when a person is under the direction of a person licensed to dispense, prescribe, administer, or furnish the substance. The relevant facts include whether the medication was lawfully prescribed to you, whether you were taking it as directed, the prescribed dosage, and whether the substance involved is the one covered by the prescription. Bring prescription bottles, pharmacy records, and prescriber information to counsel promptly; do not rely on an officer’s assumption that a medication is illicit. A prescription does not necessarily resolve separate allegations such as driving under the influence under Vehicle Code § 23152(f), which turns on impairment while driving.
What happens after an HS § 11550 arrest in Los Angeles County?
After an LAPD or LASD arrest, you may be cited and released, booked, or released with a future court date depending on the circumstances and any other allegations. The charging agency may be the Los Angeles City Attorney for many misdemeanor cases within the City of Los Angeles or the Los Angeles County District Attorney in other jurisdictions or where related allegations warrant its involvement. Counsel should obtain the arrest report, body-camera footage, testing records, dispatch logs, and any drug-recognition materials before deciding whether to contest the evidence, seek suppression under Penal Code § 1538.5, or pursue diversion. For case-specific help, Rubin Law, P.C. can be reached at (213) 723-2337.
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