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    Pennsylvania Search & Seizure Law in Criminal Drug & Gun Cases in Philadelphia – Collective Knowledge Doctrine

    Collective Knowledge in Search & Seizure Criminal Cases in PA

    Last month, the Pennsylvania Supreme Court ruled on the application of the collective knowledge rule in search and seizure cases. Under this rule, what one officer knows (relating to reasonable suspicion or probable cause) gets imputed to another officer. The question is whether there has to be a specific transfer of knowledge. In the January 2018 case, Commonwealth v. Yong, the court ruled that a specific transfer of knowledge does not need to occur if the officers are part of the same, coordinated investigation.

    Here’s a look at how the collective doctrine knowledge comes into play in a Philadelphia drug/gun case. Officer A sees a Philly resident in West Philly conduct an alleged hand to hand drug transaction, but does not arrest the resident at that time. The next day, Officer B encounters the same resident independently, i.e., without knowing that Officer A saw an alleged drug transaction involving the same individual. Officer B stops and frisks the individual and finds a gun and several bags of drugs. There was no basis for the stop/frisk because Officer A did not tell Officer B about what he had witnessed.

    Under the collective knowledge doctrine, the stop/frisk and resulting search would probably be illegal or unconstitutional because Officer A never relayed his observations to Officer B. Officer B stopped and frisked the individual without any basis to do so.

    Brief Note About Pat-Down Law in Pennsylvania Criminal Cases – When Can an Officer Stop and Frisk a Philadelphia Resident?

    In Terry v. Ohio, the U.S. Supreme Court held that a police officer can conduct a “limited pat-down search for weapons when the officer has a reasonable suspicion that the individual is armed and dangerous.” This forms the basis of all stops by an officer, whether it’s for questioning a suspect or a witness.

    But what about people who are merely present when another person gets arrested or when a search warrant is being executed at a home? Pennsylvania courts have indicated that simply being present when a search warrant is executed is not enough, in and of itself, to justify this type of pat-down under both the 4th Amendment to the U.S. Constitution and Article 1, Section 8 of the Pennsylvania Constitution. See e.g., In re J.V., PA Superior Court (2000).

    Therefore, in Pennsylvania, a police officer may stop an individual and conduct a pat-down if the officer has reasonable suspicion that the individual is armed and dangerous.

    More: Can You Be Charged with Drug Possession in Philadelphia When the Drugs Were Not Found on You? (January 17, 2018)

    Collective Knowledge Doctrine – Specific Transfer of Knowledge NO LONGER Required in PA

    City Hall downtown Philadelphia PAHistorically in Pennsylvania and in other jurisdictions, the collective knowledge doctrine has been applied narrowly. A warrantless arrest or stop/frisk without reasonable suspicion may be upheld when there’s evidence that an officer directs or otherwise authorizes another officer to make the arrest or stop/frisk.

    For example, in Comm. v. Kenney (Pennsylvania Supreme Court, 1972), a warrantless arrest was upheld where the arresting officer was actually instructed to do so by a lieutenant who had probable cause to believe the person being arrested committed a crime. There was a specific transfer of knowledge by one officer, who had probable cause, to the officer who made the actual arrest.

    This type of narrow approach to the collective knowledge doctrine is known as the vertical approach. The broader and more pro-officer/prosecution approach is the horizontal approach, where knowledge of a team of police officers is viewed in the aggregate. What one officer knows is indirectly transferred to another, even though there’s no evidence that the one officer specifically instructed the other officer about the facts giving rise to probable cause to arrest or reasonable suspicion to stop and frisk.

    In the recent PA Supreme Court case, the court made it harder for defendants to argue that a search, stop/frisk or warrantless arrest was illegal. In Comm. v. Yong, the court held that a specific transfer of knowledge is no longer required if the officers are part of the same investigation, unit, team, etc.

    So, using the example above, if Officer A and Officer B were part of the same unit or investigation and there’s at least some evidence that they met or otherwise were briefed about the arrested individual, Officer B’s stop/frisk and arrest would be allowed, because Officer A saw the alleged drug transaction.

    This certainly makes it easier for police officers in Philadelphia to stop/frisk or arrest individuals. Ultimately, this ruling whittles away at 4th Amendment protections. For more info, visit the Pennsylvania Search & Seizure Law Library.

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