Does Probable Cause Apply to Pennsylvania DUI Stops?

Get a Free Consultation
dui stop pennsylvania pa

In the Keystone State and elsewhere in the United States, probable cause is the key issue in the arrest process, even in DUI stops. The police need probable cause to make an arrest. But what is probable cause and when do police have it during a DUI stop in Pennsylvania? For more information on this subject, please continue reading, then contact an experienced Pittsburgh first DUI lawyer today.

What constitutes probable cause in Pennsylvania?

To establish probable cause, police officers must have the ability to point to objective circumstances leading them to believe that a suspect committed a crime. A police officer can’t establish probable cause by claiming intuition or “hunches.” That said, judges, not law enforcement, have the final say on whether or not probable cause exists. In spite of a police officer’s sincerity, the judge may examine that same information and disagree, thus deciding that probable cause does or did not exist.

Please keep in mind that probable cause may have existed at the time of an arrest even if the defendant didn’t actually violate the law. You see, an arrest is valid so long as officers predicate it on probable cause, even if the arrested person is innocent.

How much information do police need for probable cause in Pennsylvania?

Probable cause is an abstract concept, meaning that a firm definition will forever remain elusive. Courts have to determine case by case whether or not the police had probable cause for an arrest. In general, though, probable cause requires more than mere suspicion that a suspect committed a crime, but not as much information as one would need to prove the suspect guilty beyond a reasonable doubt.

What are some examples of probable cause?

The legality of a DUI prosecution depends – among other factors – on whether the stop and subsequent arrest were reasonable. An officer does not have to specifically suspect that the driver is under the influence of alcohol. Any potential traffic infraction or violation is enough. Examples of reasonable suspicion for a DUI stop include:

  • Straddling the centerline
  • Making an illegal turn
  • Drifting from one lane to another
  • Extremely slow or erratic driving, and/or
  • Frequent braking

If the officer still suspects the motorist of DUI after the initial investigation, he or she may then usually carry out a field sobriety test and a breathalyzer test. Note that even if a motorist is intoxicated while driving, a DUI case against him or her may be dismissed if the officer did not have probable cause for the initial stop.

If you have any further questions or would like assistance planning your defense, please reach out to a skilled Allegheny County DUI lawyer.

Contact Our Pittsburgh DUI Lawyer

If you are facing a DUI charge, contact The Law Offices of George Heym to schedule your free initial consultation.

Contact Us

Client Testimonials

“DUI case June 28, 2011- I extremely recommend hiring George Heym. He was entirely honest and great at spending thorough time on the phone. He gave me his personal cell phone so that any time, day or night if I was nervous or had a question about something, he would be able to answer it. Before I eve...”


“The Pennsylvania DUI legal process is much more complicated and confusing than I would expect. George made this process easy to navigate and helped to make things as straightforward as they could be for me. I was trying to deal with the legal process of getting a DUI in Pennsylvania after moving out...”