If you were stopped by police in Mesa and asked to perform field sobriety tests, you may already be facing serious legal exposure. Many people assume these tests are only used in alcohol DUI cases. In reality, officers throughout Mesa and Maricopa County frequently use field sobriety tests during drug investigations, including marijuana, prescription medication, and other controlled substances.
If you were arrested, speaking with a criminal defense attorney Arizona residents trust is critical. Drug-related DUI and possession cases can carry harsh penalties — and the evidence gathered during roadside testing is often more subjective than people realize.
What Are Field Sobriety Tests?
Field sobriety tests (FSTs) are roadside exercises used by law enforcement to determine whether a driver may be impaired. In Mesa, officers are trained to administer standardized tests developed by the National Highway Traffic Safety Administration (NHTSA), including:
- Horizontal Gaze Nystagmus (HGN) – Following a pen or light with your eyes
- Walk-and-Turn – Taking heel-to-toe steps along a straight line
- One-Leg Stand – Standing on one foot while counting
Although these tests are presented as scientific, they are highly subjective and depend heavily on officer interpretation.
When drugs are suspected instead of alcohol, officers may also request evaluation by a Drug Recognition Expert (DRE).
Can You Be Arrested for Drugs Based on Field Sobriety Tests Alone?
Yes — but the arrest must still be supported by probable cause.
Under Arizona Revised Statutes § 28-1381, it is illegal to:
- Drive while impaired to the slightest degree by alcohol or drugs
- Drive with certain drugs or their metabolites in your system
- Drive under the influence of prescription medication if it impairs you
Unlike alcohol DUIs, Arizona does not require proof of a specific legal limit for most drugs. Prosecutors often rely on:
- Officer observations
- Field sobriety test performance
- Statements made during the stop
- Blood test results
However, poor performance on field sobriety tests does not automatically mean impairment. Fatigue, anxiety, medical conditions, uneven pavement, and even flashing patrol lights can affect results.
How Drug Arrests Happen in Mesa
Mesa police may initiate a stop for:
- Speeding or traffic violations
- Equipment issues such as broken taillights
- Suspicion of reckless driving
- Reports of erratic driving
From there, an officer may claim to observe:
- Red or watery eyes
- Slow speech
- Delayed responses
- Odor of marijuana
This often leads to roadside testing and potentially a blood draw.
In Arizona, officers can obtain a warrant quickly for blood testing if you refuse. That blood analysis becomes a central piece of evidence in drug DUI prosecutions.
Common Drug Charges Associated with Field Sobriety Stops
A roadside investigation in Mesa can expand beyond DUI. Officers may search a vehicle and file additional charges such as:
Drug Possession – A.R.S. § 13-3407
Possession of a dangerous drug can be charged as a felony, even for small amounts.
Possession for Sale or Transportation for Sale
If officers believe the quantity or packaging suggests intent to sell, charges escalate dramatically.
Drug Paraphernalia – A.R.S. § 13-3415
Pipes, baggies, scales, or other items can lead to separate charges.
If you’re facing these accusations, you need an experienced drug crimes defense attorney who understands both DUI law and felony drug statutes.
What Happens After a Felony Drug Arrest in Arizona?
Many people search: What happens after a felony arrest in Arizona?
Here’s a simplified overview:
- Arrest and Booking – You are taken into custody and processed.
- Initial Appearance – A judge sets release conditions.
- Charging Decision – The prosecutor files formal charges.
- Pretrial Proceedings – Motions, evidence review, negotiations.
- Trial or Resolution – The case is dismissed, reduced, or goes to trial.
Drug-related DUI cases can carry:
- Jail or prison time
- Heavy fines
- Mandatory classes or treatment
- Driver’s license suspension
- Felony record
Penalties increase significantly if there are prior convictions or aggravating factors.
Defenses to Field Sobriety-Based Drug Arrests
An aggressive felony defense attorney will analyze every aspect of the stop, including:
- Was the traffic stop lawful?
- Were field sobriety tests administered correctly?
- Was there probable cause for arrest?
- Was the blood draw legally obtained?
- Were testing procedures properly followed?
Challenging procedure errors, improper searches, or unreliable testing can significantly weaken the prosecution’s case.
Why Early Legal Representation Matters
The hours and days after an arrest are critical.
A strategic criminal defense attorney Arizona residents rely on can:
- Intervene before formal charges are filed
- Preserve surveillance or bodycam footage
- Challenge improper searches
- Protect you from making damaging statements
- Develop a proactive defense strategy
Waiting can mean lost evidence and fewer options.
FAQs About Field Sobriety Tests and Drug Arrests in Mesa
Are field sobriety tests mandatory in Arizona?
No. You are not legally required to perform roadside field sobriety tests. However, refusing may still lead to arrest if the officer believes probable cause exists.
How are drug charges prosecuted in Arizona?
Prosecutors rely heavily on officer testimony, lab results, and circumstantial evidence. Unlike alcohol DUIs, drug cases often center on subjective observations and toxicology interpretation.
Can I be charged even if marijuana is legal in Arizona?
Yes. While recreational marijuana is legal under state law, driving while impaired remains illegal.
What if prescription medication caused the impairment?
You can still be charged if the medication impaired your ability to drive safely.
Facing Drug or DUI Charges in Mesa? Guardian Law Is Ready to Defend You.
Drug-related DUI arrests can quickly escalate into serious felony charges. Whether you are under investigation or have already been charged, you need a results-driven, aggressive defense strategy.
Guardian Law focuses exclusively on serious felony cases — including drug crimes, violent offenses, weapons charges, robbery defense, and white collar crime defense throughout Mesa, Phoenix, Scottsdale, and across Maricopa County.
If you or a loved one has been arrested after field sobriety testing in Mesa, do not wait.
Call Guardian Law today at (602) 888-8020 for a confidential consultation.