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Differences between reasonable suspicion and probable cause

On Behalf of | May 10, 2022 | Drunk Driving

Law enforcement officers have a duty to ensure that they’re not violating anyone’s rights as they interact with them during the criminal justice process. This means that they can’t conduct traffic stops or arrest individuals for malicious purposes. 

One thing that some defendants don’t understand is that probable cause and reasonable suspicion are different concepts that serve different purposes in this process. Understanding those differences can help you to determine if anything is amiss. 

They require 2 different levels of proof

The main difference between reasonable suspicion and probable cause is the amount of proof needed for each one. Reasonable suspicion doesn’t involve the same, higher level of proof as probable cause. An officer can merely think that a circumstance appears illegal and be able to act on their suspicions, so long as the average person with their training and experience would agree their suspicions are reasonable. For example, they can see a car swerving while speeding and initiate a traffic stop to find out if the driver is impaired by drugs or alcohol.

Police officers can’t, however, arrest a person based on reasonable suspicion. Instead, they need proof that a crime has likely occurred to meet the standard of probable cause. Using the drunk driving example, probable cause for arresting a driver for impaired driving could be the driver getting a blood alcohol concentration result that’s higher than the acceptable legal limit of 0.08%.

The actions of law enforcement officers when they’re investigating a crime, arresting a person, or interacting with a defendant after an arrest can play a role in the criminal justice process. Any defendant who believes that law enforcement violated their rights at any part in the process should discuss the case with someone who’s familiar with these matters.