Health & Safety Code 11550 makes it a misdemeanor to use, or be under the influence of, a controlled substance — no drugs have to be found on you.
It carries up to one year in county jail, but it is one of the most diversion-friendly charges in the code.
What HS 11550 Says
HS 11550 covers being under the influence of a controlled substance in violation of the law. Unlike possession (HS 11377), no drugs need to be found — the case rests on the officer’s observations and, often, a chemical test. That makes the evidence uniquely contestable.
Penalties
HS 11550 is a misdemeanor. A conviction carries a term of not more than one year in county jail, and courts frequently structure these cases around treatment rather than custody.
Defenses and Diversion
- The evidence of intoxication is thin. Officer observations and field symptoms are subjective; a chemical test can be challenged for procedure and interpretation.
- Unlawful detention. If the stop was bad, a motion to suppress under PC 1538.5 can end the case.
- No current use. The statute reaches being under the influence at the time — not past use.
- Drug-related judicial diversion (PC 1001.95) and mental health diversion (PC 1001.36) both end in dismissal, and HS 11550 is a classic candidate. See our drug defense page.
Frequently Asked Questions
Can you be charged with HS 11550 if no drugs were found?
Yes. HS 11550 punishes being under the influence of a controlled substance, so no drugs need to be found on you. The case rests on the officer's observations and often a chemical test — both of which can be challenged.
Is HS 11550 a felony or a misdemeanor?
It is a misdemeanor, carrying a term of not more than one year in county jail. Courts frequently structure these cases around treatment and diversion rather than custody.
Can an HS 11550 charge be dismissed?
Often. It is one of the most diversion-friendly charges in the code — judicial diversion (PC 1001.95) and mental health diversion (PC 1001.36) both end in dismissal. If the stop was unlawful, a motion to suppress under PC 1538.5 can also end the case.
What is the difference between HS 11550 and HS 11377?
HS 11377 is possession of a controlled substance (the drugs are found on you). HS 11550 is being under the influence — no drugs need to be found. The two are sometimes charged together and are defended in overlapping ways.
GuidesComplete Guide to California Misdemeanors · Glossary · Penalties Reference.
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Ahmed S. Hasan
San Francisco Criminal Defense Attorney · State Bar of California #364992
Ahmed S. Hasan is the founder of ASH Legal, a solo criminal defense practice based in San Francisco. The firm runs on flat-fee representation: one lawyer, one fee, from arraignment through resolution. No hourly billing. No surprise invoices.
Ahmed is a graduate of Emory University School of Law and a member in good standing of the State Bar of California (Bar #364992). His practice focuses on San Francisco misdemeanor defense — DUI, domestic violence, petty theft and shoplifting, drug possession, vandalism, trespassing, and assault and battery — with particular attention to diversion-track outcomes that end in dismissal under PC 1001.95, PC 1001.36 (Mental Health Diversion), PC 1001.80 (Military Diversion), and PC 1001.83 (Parental Caregiver Diversion).
Ahmed previously served as a post-bar clerk with the San Francisco Public Defender's Office, the city's largest indigent-defense practice. He is a member of the Asian Pacific American Bar Association of Silicon Valley.
He represents clients at the San Francisco Hall of Justice (850 Bryant Street) and the Civic Center Courthouse. The ASH Legal office is at 15 Boardman Place, Suite 301, San Francisco, CA 94103.
Free 30-minute consultations are available by phone or Zoom. (510) 545-6515 · ahmed@ashlegal.com