×

Address

Demystifying Law Enforcement Standards: Reasonable Suspicion vs. Probable Cause

There are two legal concepts police officers must establish in order to detain someone, arrest someone, or conduct a search and seize evidence: reasonable suspicion and probable cause. While both standards were set by the U.S. Supreme Court and share similarities, there are major differences between the two concepts.

Reasonable Suspicion

Reasonable Suspicion

The U.S. Supreme Court ruled in 1968 that law enforcement officials can briefly detain an individual if the officer has “reasonable suspicion” that a crime has occurred, is currently happening, or is going to be committed later. If reasonable suspicion exists, then a law enforcement official can detain, frisk, and question the alleged suspect.

Although reasonable suspicion is subjective to some extent, it is more than a gut feeling or inkling. Rather, reasonable suspicion is based on the facts and circumstances, as well as an officer’s relevant training and experience.

For example, an officer driving a police vehicle notices another car having difficulty maintaining proper lane position without its headlights on. Based on the officer’s observations backed by his/her training and experience, he/she has reasonable suspicion that the driver may be driving under the influence of alcohol or drugs and can pull the driver over.

Probable Cause

However, the officer cannot arrest the driver or search his/her vehicle without probable cause. Establishing probable cause also gives the police the power to obtain a warrant.

According to a 1949 ruling, the U.S. Supreme Court established that probable cause exists if there is logical belief – based on supported facts and circumstances – that a crime has occurred, is currently happening, or is going to be committed later. In other words, the standard for probable cause is that any “reasonable person” may believe that there is evidence of criminal activity, instead of any “reasonable officer” may suspect such activity.

Returning to the example mentioned above, after the officer pulls the driver over, if the officer observes that there is a smell of alcohol coming from inside the vehicle, the driver is slurring his/her words, and has difficulty clearly responding to questions, any reasonable person may suspect that the driver is under the influence. The officer now has reasonable suspicion to arrest the suspected drunk/drugged driver.

If you or a loved one has been arrested in Albany, contact O’Brien & Eggleston PLLC today and schedule a free consultation. Our legal team has more than 20 years of combined legal experience! 

Related Posts


Your Fourth Amendment Rights: How to Fight Illegal Searches and Seizures in Binghamton, New York

The Fourth Amendment of the U.S. Constitution protects individuals from unreasonable searches and seizures by law enforcement. Police cannot search your home, vehicle, or person…

Money Laundering Charges: How to Defend Complex Financial Crime Allegations

Money laundering is a serious federal and state offense with severe penalties, including substantial fines, asset forfeiture, and long prison sentences. Prosecutors pursue these cases…

How to Fight Drug Charges in a College Setting: What Students Need to Know

Life on campus comes with new experiences and social interactions for many college students. However, if a student is arrested for drug possession, distribution, or…

The information on this website is for general information purposes only. Nothing on this site should be taken as legal advice for any individual case or situation. This information is not intended to create, and receipt or viewing does not constitute, an attorney-client relationship.

© 2025 All Rights Reserved.

amn-logo