A New Hampshire police officer must establish probable cause to make a drunk driving arrest. If the arrest occurs in conjunction with a traffic stop, the officer must have also had reasonable cause to stop the driver, such as witnessing a vehicle veering over the yellow line. Arresting someone for suspected DUI without probable cause violates the Fourth Amendment of the U.S. Constitution.
The Fourth Amendment protects people against unlawful search and seizure. When a police officer makes a traffic stop and instructs the driver to exit the vehicle due to suspected intoxication, the driver is being detained. This is why taking a person into custody without probable cause is the same as an unlawful seizure. An arrest is the “seizure” of a person.
Establishing probable cause for a DUI arrest
To demonstrate probable cause, a police officer must be able to prove that the information he or she knew at the time would have led a reasonable person to suspect that a crime had been or was being committed. The breath test detects the presence of alcohol on a person’s breath. If an individual is unable to pass a preliminary alcohol screening test, it is logical for a police officer to suspect intoxication.
What to do if an unlawful arrest takes place
Lack of probable cause is not the only issue that constitutes an unlawful DUI arrest. For example, if a police officer did not have a legitimate reason to initiate a traffic stop, then arresting someone for DUI as part of that stop may be considered unlawful. The best thing to do if an unlawful arrest has taken place is to remain calm and request legal support so that an experienced defense attorney can review the case and recommend the best course of action.