Reasonable Suspicion & Probable Cause in DUI Cases

A police officer can detain a person for questioning, search for evidence, and make a DUI arrest in West Virginia if he/she establishes reasonable suspicion and probable cause. Although these two legal concepts are used interchangeably, there are several key differences.

Reasonable Suspicion

Reasonable Suspicion & Probable Cause in DUI CasesReasonable suspicion must be established in order to detain someone or make a traffic stop. This means that an officer has reason to believe—based on his/her training and experience—that a crime has been committed, is being committed, or will be committed. While reasonable suspicion is subjective in nature, law enforcement officials must have more than a hunch or gut feeling to detain someone. Certain facts and circumstances must be apparent. For example, if an officer notices that a driver commits a traffic violation (e.g. running a red light, failing to signal before making a turn or switching lanes, or driving in a night without the headlights on) or otherwise drives erratically, the officer has reasonable suspicion that the driver is intoxicated and can pull him/her over.

What is Probable Cause?

Probable cause must be established to obtain a warrant, search a vehicle, or arrest a suspected drunk driver. There needs to be enough evidence that a reasonable person would believe a crime has been, is being, or will be committed. Referring back to the example above, when the officer pulls over the vehicle and interacts with the driver, he/she notices the smell of alcohol on the driver’s breath, the driver’s speech is slurred, and the driver’s eyes are red and watery, the officer has probable cause to make a DUI arrest. The main difference between reasonable suspicion and probable cause is that the former exists if a reasonable officer may suspect criminal activity, while the latter exists if a reasonable individual (not a cop) may suspect a crime. If you have been charged with a DUI in West Virginia, contact The Wagner Law today at (304) 461-6000.
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Harley Wagner

Attorney Thomas M. Cooley School of Law, National College for DUI Defense, West Virginia State Bar

Harley has represented over 3,000 citizens throughout West Virginia. He is the author of West Virginia DUI Defense, The Law and Practice, which is the go to handbook for many magistrates, judges, defense attorneys, prosecutors, and law enforcement throughout West Virginia. has been selected for inclusion in West Virginia Super Lawyers® eight times.

He maintains an AV Preeminent® Rating by with Martindale-Hubbell®, an Avvo Rating of 10.0, and an excellent annual rating from the Better Business Bureau.

Harley is also the past president of the national DUI Defense Lawyers Association (2020-2021) which he was Charter Member and founder of in 2014

Areas of Expertise: DUI Defense, Aggravated DUI, Alternative Sentencing, Boating Under the Influence, Commercial License DUI, DMV Hearings, DUI Drugs, DUI with Injury, DUI Causing Death, Out-of-State Resident DUI, DUI Immigration Consequences, DUI with Minor in Vehicle, DUI Child Endangerment, Fleeing a DUI, Felony DUI, Permitting DUI, Underage DUI, Multiple DUI, First-Offense DUI, Second-Offense DUI, Third-Offense DUI, DUI Testing, Field Sobriety Tests, Breathalyzer, Blood Testing, DUI Info Center, College Student DUI, DUI Checkpoints, DUI Court Dates, DUI Deferral Program, Implied Consent, Test & Lock Program, FAQ, DUI Penalties, Administrative License Revocation, Ignition Interlock Device, License Suspension