What is the Difference Between Reasonable Suspicion & 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 

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! 

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