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When can a Police Officer stop a car for suspicion of DUI / Drunk Driving?

Chester County DUI Lawyer
Contact West Chester DUI lawyer and Criminal Defense Lawyer Mike DiCindio

What does a Police Officer need to observe before he is permitted to legally stop a vehicle under suspicion of DUI / drunk driving?


Under the vehicle code, a police officer in Chester County, or anywhere in Pennsylvania, may conduct an investigatory detention if he has reasonable suspicion to believe that a motorist violated a provision of the motor vehicle code.  (For example, he suspects the driver is committing a DUI or drunk driving offense)  In order to establish grounds for reasonable suspicion an officer must, “articulate specific observations which, in conjunction with reasonable inference derived from those observations, led him reasonably to conclude, in light of his experience, that criminal activity was afoot and that the person he stopped was involved in that activity.” Commonwealth v. Basinger, 982 A.2d 121, 125 (Pa. Super. 2009); Commonwealth v. Sands, 887 A. 2d 261, 272 (Pa. Super. 2005). Further, a traffic stop may be conducted based on reasonable suspicion particularly in cases where the suspicion is whether the driver is operating under the influence – or DUI / drunk driving. See, Commonwealth v. Sands, 887 A. 2d 261, 272 (Pa. Super. 2005).

When reasonable suspicion exists, a vehicle stop stop shall only be valid if the stop furthers the purpose behind the stop. Commonwealth v. Chase, 960 A.2d 108 (Pa. 2008).  In other words, the police officer must be able to gain more evidence from conducting the stop.  (Was the driving tired and that is why he was swerving or was he really DUI?  Does he smell like alcohol?  Did he just swerve by accident?)  Stopping the vehicle must provide an officer with more evidence – to further investigate, and confirm or dispel the suspicions.  In cases where the stop would not provide any more evidence that may confirm or dispel an officer’s suspicions, he/she must possess the higher standard of probable cause before pulling a vehicle over.

A criminal defense attorney must understand the law and be willing to fight for his client in every DUI case. courthouse2

In Chester County, a skilled criminal defense lawyer may be able to file a motion to suppress the stop of a vehicle in a DUI case when the evidence shows the officer did not have reasonable suspicion.  Often times, an officer may not be able to provide or testify to enough details about an individuals driving to rise to the level of reasonable suspicion.  In those cases, a criminal attorney will file the motion to suppress, take testimony of the officer, and argue to the Court that the officer conducted an illegal stop.  If the motion the defense attorney files is granted, the evidence flowing from the illegal stop is suppressed – the DUI will not be able to stand.

While, “the determination of whether an officer had reasonable suspicion that criminality was afoot so as to justify an investigatory detention is an objective one, which must be considered in light of the totality of the circumstances.” Commonwealth v. Holmes, 14 A.3d 89 (Pa. 2011); citing, Commonwealth v. Chase, 960 A.2d 108, 120 (Pa. 2008) (“[r]easonable suspicion sufficient to stop a motorist must be viewed from the standpoint of an objectively reasonable police officer” (citing, Ornelas v. United States, 517 U.S. 690 (1996))); Commonwealth v. Rogers, 849 A.2d 1185, 1189 (Pa. 2004).  It is still something that a criminal defense lawyer MUST be analyze in every DUI / drunk driving case, or in any case involving a motor vehicle stop, before proceeding.

If you have a pending DUI / drunk driving case – contact Mike DiCindio today for your free consultation.



***This blog is made available by the law firm publisher for educational purposes and to provide general information, not to provide specific legal advice.  By reading, you understand that there is no attorney client relationship between you and the publisher. The blog should not be used, nor is it meant to be, as a substitute for competent legal advice from a licensed professional attorney.***

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