Many criminal cases involving alleged drunk driving hinge on details about the traffic stop itself. This includes whether or not the police officer had reasonable suspicion (and therefore legal justification) to pull over the driver. Law enforcement officers who charge drivers with OWI do not need to suspect drunk driving when they first initiate the stop. Instead, they can pull someone over based on observed violations of traffic laws, lesser offenses such as vehicle maintenance issues or erratic driving.
The above is only a partial list. Historically, courts have given police officers a wide berth when it comes to justifiable reasons for pulling someone over. And a ruling by the Wisconsin Supreme Court earlier this month has added another stop-worthy offense to that list: littering. According to news sources, police can initiate a traffic stop for an offense as small as discarding a cigarette butt out of a car window by any occupant of the vehicle.
The case before the Court involved a driver who had been cited for first offense OWI while driving near La Crosse. The officer later said that he suspected drunk driving when he saw the man stop at flashing yellow lights in the very early hours of the morning. But he could not justify making the stop until he saw one of the vehicle's occupants discard a cigarette butt out the window.
Littering is illegal in Wisconsin, but it is a non-criminal, non-traffic offense usually punished by a fine. The Wisconsin Supreme Court held that the stop was valid and that the defendant's Fourth Amendment rights against unreasonable search and seizure were not violated. The majority opinion stated that there were "no Fourth Amendment violations since state law explicitly authorizes troopers to stop drivers for suspected littering violations," according to the Milwaukee Journal Sentinel.
There are a staggering number of laws on the books in Wisconsin and nationally. In spite of this (or perhaps because of this), many criminal cases involve disputes about how certain laws should be interpreted and when they do or do not apply.
Laws are not always as straightforward and iron-clad as you might think. For this and other reasons, anyone charged with a crime should seek the help of an experienced criminal defense attorney.