While recreational marijuana use is legal in California, driving under the influence of marijuana is not … but what is the legal limit for driving high?

The problem is that there is no scientifically measurable level of impairment that is legally “too high” when it comes to marijuana.

Unlike alcohol, where impairment is measured by a blood alcohol concentration (BAC) limit, there is no equivalent threshold for marijuana.

The law states that it is illegal to drive if marijuana consumption affects your ability to operate a vehicle safely. But determining how much a person is “under the influence” of cannabis remains subjective.

So, if you’ve been accused of driving high, understanding the law and your rights is crucial.

The Challenges of Measuring Marijuana Impairment

Detecting marijuana impairment is not as straightforward as measuring alcohol levels. THC, the psychoactive compound in cannabis, affects individuals differently based on tolerance, frequency of use, and dosage.

Like alcohol, marijuana impairs judgment, reaction time, and motor skills, increasing the risk of accidents. But while alcohol has a universal BAC standard of 0.08%, marijuana does not yet have a scientifically agreed-upon limit for impairment in California or federally.

Instead, driving under the influence of marijuana is assessed based on observed impairment. Law enforcement officers rely on behavioral observations, field sobriety tests, and sometimes drug recognition experts to identify impaired drivers.

How Does California Define Driving Under the Influence of Marijuana?

Under California Vehicle Code Section 23152(f), it is unlawful for a person to drive a vehicle while under the influence of any drug, including marijuana. “Under the influence” means that the driver’s ability to operate the vehicle safely is impaired to an appreciable degree due to the substance.

However, without clear guidelines for measuring marijuana impairment, law enforcement officers have to rely on behavioral observations such as the following:

• Observations of erratic driving or behavior.
• The smell of marijuana in the car or on the driver.
• Physical signs such as red eyes, slow speech, or poor coordination.

Drivers also may be required to undergo a blood or urine test to detect THC levels, but, again, no universally accepted legal threshold exists for determining impairment.

What Happens if You’re Pulled Over for Suspected Driving High?

If an officer suspects you of driving under the influence of marijuana, they may do one or both of the following:

1. Conduct a field sobriety test to assess physical or cognitive impairment.
2. Request a chemical test, such as a blood test, to detect THC.

Under California’s implied consent law, refusing a chemical test can result in automatic penalties, including license suspension.

Penalties for Driving High in California

Like driving under the influence of alcohol, the consequences of a DUI involving marijuana can be severe.

Penalties for a First Offense can include:

• Fines ranging from $390 to $1,000.
• License suspension for up to six months.
• Enrollment in a DUI education program.
• Possible jail time of up to six months.

Penalties for Repeat Offenses include:

• Increased fines and longer license suspension periods.
• Mandatory installation of an ignition interlock device.
• Longer DUI education programs.
• Harsher jail or prison sentences.

Combining marijuana with alcohol significantly increases impairment, which can lead to harsher penalties and greater risks to public safety. If an accident occurs while driving high, penalties can escalate to include felony charges, especially if someone is injured or killed.

Legal Defenses for Driving High

An experienced criminal defense attorney can employ several legal defenses to challenge a marijuana DUI charge. For example:

1. Lack of Evidence of Impairment. The presence of THC in your system does not necessarily indicate impairment at the time of driving, as THC can remain detectable long after its effects have worn off.
2. Improper Testing Procedures. Blood or urine tests must be conducted following strict protocols. Any deviation can render the results inadmissible in court.
3. Unreliable Field Sobriety Tests. Many factors — such as medical conditions or nervousness — can affect performance on these tests, making them unreliable indicators of impairment.
4. Violation of Rights. If the officer lacked reasonable suspicion to pull you over or failed to follow proper arrest procedures, your charges might be reduced or dismissed.

Why Hire an Experienced Criminal Defense Attorney?

If you’ve been charged with driving under the influence of marijuana, the consequences can be life-altering. An experienced criminal defense attorney can:

• Review the evidence to identify weaknesses in the prosecution’s case.
• Advocate for reduced charges or penalties.
• Represent you in court to secure the best possible outcome.

Contact Mark Broughton today for a free consultation. With decades of experience in criminal defense, Mark can help protect your rights and guide you through the legal process with compassion and expertise.

Call 559-691-6222 or click here to use our convenient online form to get legal help today.

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