Pennsylvania adheres to the vertical approach of collective knowledge. Here, another officer got involved and made the decision to arrest, but he knew what the first officer knew, and that was enough. This was still collective knowledge. (There is a lengthy discussion of vertical v. horizontal collective knowledge, that, at bottom, really doesn’t add anything to the case and is academic at best. Only two paragraphs of about eight are included here.) Commonwealth v. Yong, 2018 Pa. LEXIS 379 (Jan. 18, 2018) (4-2, -1) (dissent), rev’g 2015 PA Super 152, 120 A.3d 299 (2015):
The collective knowledge doctrine’s development in case law has created, broadly speaking, two formulas. The vertical approach has been applied with little controversy and finds support in the Supreme Court’s decision in Whiteley and this Court’s decision in Kenney. In Kenney, this Court concluded that when an officer makes an arrest on the direction of another officer, “the operative question” is not whether the arresting officer had independent probable cause to arrest but whether the officer who ordered the arrest had sufficient information to support probable cause. See Kenney, 297 A.2d at 796. Indeed, in support of the imputation of knowledge from an officer with probable cause to another carrying out a directive to arrest, we relied on the Whiteley Court’s reasoning. See id. n.3. The doctrine applied in this manner reflects the realities of police work and the need for swift action and justifiable reliance on communications in order to efficiently perform the duties attendant to law enforcement. See, e.g., Whiteley, 401 U.S. at 568 (stating, “[c]ertainly police officers … are entitled to assume that the officers requesting aid offered the magistrate the information requisite to support an independent judicial assessment of probable cause”); Hensley, 469 U.S. at 231 (“this rule is a matter of common sense: it minimizes the volume of information concerning suspects that must be transmitted to other jurisdictions and enables police officers in one jurisdiction to act promptly in reliance on information from another jurisdiction.”); see also Daniels v. United States, 393 F.2d 359, 361, 129 U.S. App. D.C. 250 (D.C. Cir. 1962) (“[t]here is no requirement that the arresting officer have sufficient firsthand knowledge to constitute probable cause. It is enough that the police officer initiating the chain of communication” has information that amounts to probable cause.); United States v. Burton, 288 F.3d 91, 99 (3d Cir. 2002) (“the arresting officer need not possess an encyclopedic knowledge of the facts supporting probable cause, but can instead rely on an instruction to arrest delivered by other officers possessing probable cause.”). This approach in assessing whether a warrantless seizure meets Fourth Amendment standards has been said to be “the best compromise” for determining whether an arrest by an officer without reasonable suspicion or probable cause is lawful because it reflects the need for a “middle ground” between affording the police some flexibility in enforcing the law and adhering to a rigid probable cause standard to protect citizens from unreasonable intrusions. Derik T. Fettig, Who Knew What When? A Critical Analysis of the Expanding Collective Knowledge Doctrine, 82 UMKC L. Rev, 663, 671-72; see also Simon Stern, Constructive Knowledge, Probable Cause, and Administrative Decisionmaking, 82 Notre Dame L. Rev. 1085, 1098 (2007) (highlighting in a “fast-paced situation” where police are pursuing several suspects, requiring “that others cannot take up chase until they receive detailed information about every suspect, … would be counterproductive.”).
In contrast to the relatively non-controversial, vertical approach, the horizontal approach “represents a broad expansion of the doctrine’s scope” and has led to circuit splits in its adoption. See id. at 672. This formulation “subsumes situations where a number of individual law enforcement officers have pieces of the probable cause puzzle, but no single officer possesses information sufficient for probable cause. … In such situations, the court must consider whether the individual officers have communicated the information they possess individually, thereby pooling their collective knowledge to meet the probable cause threshold.” United States v. Chavez, 534 F.3d 1338, 1345 (10th Cir. 2008). However, not every application of a purely non-vertical approach arises in the same factual manner. Some courts applying the collective knowledge doctrine impute knowledge in the absence of an explicit direction to act or transfer of information so long as there is “some communication” among the officers and they are acting in a coordinated investigation. In United States v. Randy Terry, 400 F.3d 575 (8th Cir. 2005), for example, officers were responding to a call to investigate a domestic disturbance. Upon briefly detaining Terry based on the description of his vehicle, one officer observed ammunition and searched Terry’s truck, uncovering contraband. Contemporaneously, another officer, who at the time was speaking to Terry’s wife, had knowledge of a protective order against Terry. Terry argued that the officer who searched his vehicle could not have done so in accord with Fourth Amendment protections because the “incriminating nature of the ammunition could not have been immediately apparent” without knowledge of the protective order. Id. at 580. The Eighth Circuit noted the district court’s finding that the searching officer had knowledge of the protective order was “not entirely without foundation in the record.” Id. However, it continued that under its approach to the collective knowledge doctrine, the actual knowledge of the searching officer, or whether he was acting at the direction of another officer’s command, were not dispositive of the Fourth Amendment inquiry.
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Although we decline to adopt a sweeping rule authorizing the imputation of knowledge between officers without direction or communication, this case presents us with what we regard as a modest amplification of the vertical application of the collective knowledge doctrine. In the instant case it is undisputed Officer McCook had probable cause to arrest Yong, and that Officer Gibson was with Officer McCook at the scene working to execute the search warrant after Officer McCook had briefed him and his companions on the efforts, at the time Officer Gibson arrested Yong. See N.T. Suppression Hr’g, 4/17/13, at 4-5. This case bears similarity to United States v. Ragsdale, 470 F.2d 24 (5th Cir. 1972). In Ragsdale, two officers conducted a traffic stop based on Ragsdale’s speeding. Upon asking Ragsdale to exit his vehicle, Officer Jones observed a hand gun in the car. Officer Jones whispered this to his partner, Officer Mullens; however, he admittedly did not hear the comment, but nevertheless undertook a warrantless search of the vehicle.