Sometimes it seems that law enforcement can stop someone for any reason. However, the Fourth Amendment says that officers must have reasonable suspicion to legally stop and probable cause to search someone. While the two terms seem to mean the same thing, they apply to different actions.
Reasonable suspicion is broader
While officers may pull someone over for erratic driving or speeding, they do not need the driver to violate the law to reasonably suspect that the driver might be committing criminal activities.
They may briefly detain the motorist for a limited investigation of the facts. It does not include a lengthy interrogation, but it could involve conducting a sobriety test, speaking with the driver, or conducting a general inspection. While the parameters are broader than this list, valid examples of reasonable suspicion include:
- Erratic driving
- Illegal turns
- Speeding
- Causing a collision
- Frequent braking
Any of these could lead to the suspicion that the driver is impaired, but reasonable suspicion cannot in itself justify an arrest. For that, the officer needs probable cause.
Probable cause is more specific
There is a higher standard for probable cause. There must be enough evidence to lead the officer to conclude that there is likely criminal activity. This justifies an arrest. While reasonable suspicion would be erratic driving, probable cause would involve the driver failing a sobriety test or breathalyzer test in the field. Probable cause leads to an initial search and the seizure of property.
The officer’s judgment could be questioned
It is common for defense attorneys to question the validity of a traffic stop or arrest. Officers are trained law enforcement professionals, but they can also make mistakes or allow biases to cloud their thinking. They must have a reason for the stop that is more than “just a hunch.” The lawyer can challenge the validity of the officer’s reasonable suspicion or probable cause. Failure to establish probable cause can lead to getting the case dismissed.