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The “Collective Knowledge” Doctrine in D.C.

Jamison KoehlerEvidence, Opinions/Cases


The firmly established “collective knowledge” doctrine in D.C. provides that, in determining whether the officers possessed sufficient knowledge to establish reasonable suspicion or probable cause for a search or seizure, it is not what any individual officer knows but what the officers know collectively, whether or not the information is actually communicated from one officer to another. At the same time, possessing the requisite information from police officers viewed collectively does not relieve the government of its burden to introduce this information either at trial or during a pre-trial motion to suppress.  This is the holding from Parsons v. United States, ___ A.2d ___ (D.C. 2011), a D.C. Court of Appeals decision that was issued on Thursday.

On May 2008, a paid informant to the U.S. Park Police called his “main handler,” Detective Freeman, to report a “narcotics violation” in the 300 block of Livingston Terrace, Southeast. However, because Detective Freeman was off duty at the time, the detective instructed the informant to provide the information to one of the detective’s colleagues, Wayne Humberson.

Acting on the informant’s tip, Detective Humberson went to the location in question and, finding Parson there matching the description, stopped and searched him. The Detective found a pink zip-lock bag containing cocaine in Parson’s left sock. Parsons was then arrested and charged with unlawful possession of a controlled substance in violation of D.C. Code § 48-904.01(d).

Parson’s lawyer did not file a pre-trial motion to challenge the legality of either the stop or the search.  However, when it became apparent during trial that Detective Humberson had never worked with the informant before and therefore had no way to gauge his reliability, defense counsel immediately made an oral motion to suppress the search.  He argued that, because Humberson did not personally know the informant to be reliable, “the reason for stopping Mr. Parson[s] was not justified.”

The judge denied the motion, holding that on the basis of the collective knowledge doctrine, Detective Humberson “[did]n’t have to know that [the source was] reliable . . . He [did]n’t have to know it personally . . . What one knows, they all know.”

The problem was with the government’s case, however, and the reason that Parson’s convicted was overturned and his case remanded for trial was that, even though one officer possessed the necessary information on the informant’s reliability and this information could be imputed to the officer who effect the search, the government is still not relieved of its duty to produce this evidence for the court.  And this the government failed to do. The court held:

The problem in the present case is that, even applying the collective knowledge doctrine, there was no testimony from which the trial court could have judged the informant’s credibility. Detective Humberson was not the confidential informant’s handler; in fact he had never dealt with the informant prior to the day of Parsons’s arrest. Detective Freeman, who was the handler, presumably could have testified at Parsons’s trial as to the informant’s track record and the existence of other virtuous qualities, but he did not. It appears from the record that the trial court “simply rel[ied] on [Detective Humberson’s] conclusory assertions in deciding whether [his search of Parsons] was justified” and did not, as required by our case law, “evaluate the facts underlying those assertions.”