There are hundreds of thousands of cars on the road in St. Charles County every day. With so many motorists and so many road-miles, police officers and motorists are regularly in face-to-face contact. When it comes to arrest for DWI, any St. Charles DWI lawyer will inquire as to whether the officer adequately arrived at probable cause.
Probable cause is the standard for making most all arrests. So before a police officer may arrest a motorist for driving while intoxicated, he or she must first have probable cause that such a motorist was doing so.
Essentially, probable cause means there's a reasonable believe a person has committed a crime. To unpack such a nebulous concept, and parse out the assumptions interior to a concept chief to our republic, probable cause requires a reasonable amount of suspicion, supported by circumstances sufficiently strong to justify a prudent and cautious person's belief that certain facts are probably true.
So before a driver gets his or her DWI ticket, a host of constitutionally-required steps must occur. A police officer may not simply pull over drivers on a hunch or at random to check if they are drunk. A police officer must have a reason for the stop in the first place. That is to say, if a driver is improperly using traffic lanes (known colloquially as "weaving"), then the officer may initiate a traffic stop for the weaving. However, such a traffic infraction doesn't translate to DWI.
Officers must follow steps outlined by case law, statutes and agency rules in determining if probable cause for further and more serious charges is present. So a speeding charge may lead to an officer smelling liquor. However, that alone is not enough to order a breath test. The officer has a series of observations and performance tests he must go through to build further upon the probable cause requirement. If a person fails a walking the line test, slurs his speech, smells of alcohol and has bloodshot eyes, the law officer likely has enough probable cause to order a breathalyzer test. Note that a failed breathalyzer test is merely probable cause that a driver was driving drunk and not that he was guilty of driving drunk. Most people believe a failed breath test is the end of the story. However, any St. Charles DWI lawyer will tell you that analysis of the machine, its maintenance and officer proficiency all may adversely affect the suspect's test outcome.
So theoretically, an officer could pull over a driver who was weaving because he was leaning over to pick up a jar of paint chemicals that had spilled. The chemicals fumes smelled to the officer like alcohol. The driver had a physical limitation with his ability to walk toe-to-toe and also slurred his speech stemming from another physical limitation. The officer orders a breath test and the driver submits to the breath test. It reads .00, i.e., no blood alcohol content. Is the officer out of line? Likely not. So long as he or she went through the steps, got results that a legal standard calls for further DWI inquiry and then goes legitimately all the way to the breathalyzer, that's the way probable cause functions. Remember, it's probable cause, not certain cause.
However, if a person truly driving drunk is pulled over for weaving. The officer recognizes the person upon approaching the stopped vehicle and knows the driver has a reputation for heavy drinking. Then the officer delivers the driver to the police station for breath test. The officer likely has failed to satisfy the standards of probable cause. If you have further interest in the subject that is not addressed here, please read more about this topic at our other Show Me the Law blogs for further description and elucidation. Or contact an attorney for advice specific to your special situation and legal matter.
Bryan C. Edwards is a St. Charles DWI Lawyer and practices criminal defense law across the St. Louis metro area, including St. Charles County, St. Louis City and St. Louis County with a consortium of attorneys around the state of Missouri at www.showmelawyergroup.com.
