Background
On the night of January 22, 2023, Montgomery County Detective Sergeant Peter Muollo received a call on his personal cell phone from a woman he had known personally for 20 to 25 years. She reported a “suspicious black sedan” parked on Rosebay Court—a dead-end street in a Germantown, Maryland townhome community where she lived—describing the car as unfamiliar, sitting there for “an extended period of time” with “cell phones going on and off” inside. She said she thought the occupants “were up to illegal activity, possibly breaking into vehicles.” The call was not recorded, and the caller asked to remain anonymous. No notes were taken.
Sgt. Muollo arrived within ten minutes and found a black sedan matching the description parked at the end of the dead-end street. Three marked police vehicles converged and took staggered positions behind the sedan, effectively boxing it in. Sgt. Muollo activated a spotlight and began approaching on foot. The sedan then moved slowly—5 to 10 mph—toward the dead end in what Sgt. Muollo himself believed was an attempt to make a three-point turn. He returned to his cruiser and activated his emergency lights, initiating a stop. Upon approaching the car, he detected a strong odor of marijuana; a colleague observed a large quantity on the back seat. The driver, Xavier Kopp, voluntarily disclosed he was carrying a firearm. Kopp was arrested and charged with firearms and marijuana offenses.
Kopp moved to suppress all evidence, arguing the stop lacked reasonable suspicion. The Circuit Court for Montgomery County denied the motion, finding reasonable suspicion based on the tip, a “significant level of crime” in the area, and the car’s movement. After that ruling, Kopp entered a conditional guilty plea to possession of a regulated firearm by a person under 21 and was sentenced to five years, all but six months suspended, plus three years of supervised probation. The Appellate Court of Maryland affirmed. The Supreme Court of Maryland granted certiorari.
The Court’s Holding
The Supreme Court of Maryland reversed, holding that under the totality of the circumstances, Sgt. Muollo lacked reasonable suspicion to stop Kopp’s vehicle. Writing for the Court, Justice Watts held that although a tip from a known and personally credible caller can carry more weight than a purely anonymous tip, the caller’s veracity alone does not supply the missing element of basis of knowledge. The tip here conveyed only that an unfamiliar car had been parked on the street for some unspecified “extended period” while occupants used their cell phones—conduct entirely consistent with innocent behavior. The caller offered no information explaining how she concluded the occupants were engaged in criminal activity, and Sgt. Muollo’s corroboration confirmed only the car’s presence, an innocent detail that added nothing to the tip’s reliability regarding criminality.
The Court reaffirmed its holding in Washington v. State, 482 Md. 395 (2022), that testimony supporting a “high-crime area” designation must be particularized as to the specific geographic location at issue, the particular types of criminal activity known to occur there, and the temporal proximity of that activity to the time of the stop. The Court found the State’s evidence fatally deficient: Sgt. Muollo’s testimony relied on aggregate “calls for service” for the entire “Nancy-1 beat”—a geographic area three to four miles long and up to two miles wide encompassing multiple neighborhoods. Defense counsel’s own analysis showed that in the 13-month period covering the stop, there was a single call for service on any of the twelve streets nearest to Rosebay Court, and that call was for a larceny under $50 from several months earlier. Raw calls-for-service counts, without more, do not establish that a specific location is a high-crime area.
Finally, the Court held that the sedan’s slow movement—which Sgt. Muollo himself attributed to an apparent three-point turn—did not constitute flight and added nothing to the reasonable suspicion calculus. Because none of the three factors relied upon by the lower courts—the tip, the high-crime area designation, or the car’s movement—individually or collectively supplied the required particularized and objective basis for suspecting criminal activity, the stop was unconstitutional and the motion to suppress should have been granted.
Key Takeaways
- A tip from a personally known, credible caller still requires a discernible basis of knowledge—the caller must convey some factual foundation for suspecting criminality, not merely describe innocent behavior with a speculative conclusion.
- Police corroboration that confirms only innocent details predicted by a tip (e.g., the car was where the caller said it would be) does not supply the reliability needed for reasonable suspicion; corroboration must tend to confirm the criminal nature of the activity.
- Under Washington v. State, a high-crime area designation requires testimony particularized to the specific location, specific crime types, and recent time period—broad beat-level “calls for service” statistics do not suffice, and the suspect’s conduct must be consistent with the crimes that allegedly make the area high-crime.
- A vehicle moving slowly away from approaching officers in a manner the officer himself interprets as a three-point turn does not constitute flight and cannot meaningfully contribute to reasonable suspicion.
Why It Matters
This decision significantly tightens the standards Maryland courts must apply when police rely on community tips and neighborhood crime statistics to justify Terry stops. By insisting that even known-caller tips must demonstrate a credible basis for inferring criminality—not just describe ambiguous observations—the Court reinforces that the Fourth Amendment’s particularity requirement does not dissolve when a tipster happens to be personally known to the officer. Defense attorneys can now cite Kopp to challenge stops premised on vague “suspicious” reports that describe nothing more than an unfamiliar vehicle or people using their phones.
The Court’s rigorous application of Washington v. State‘s high-crime area framework is equally significant. Prosecutors and law enforcement agencies in Maryland will need to present location-specific, crime-specific, and temporally proximate data to invoke the high-crime area factor—broad precinct-level or beat-level call tallies will no longer carry that weight. Together, these holdings push back against the aggregation of weak inference upon weak inference in totality-of-the-circumstances analysis, a practice that courts have sometimes allowed to erode the reasonable suspicion threshold.