The defense argued that the December 9 stop and the search of Mangione’s backpack violated the Fourth Amendment. It contended officers lacked a valid basis to detain him and search his belongings, and that anything recovered — the firearm, the notebook, and identification documents — should be excluded as fruit of an unlawful search.

Prosecutors responded that officers had reasonable suspicion when they approached, that Mangione was lawfully arrested, and that the notebook and pistol were properly recovered incident to that arrest. They asked the court to admit all of the seized evidence.

The suppression hearing turned on the sequence of the stop: when the detention began, what officers knew at each step, and which items were in plain view versus discovered through a fuller search of the bag.

Admitting the pistol and notebook keeps the state’s central physical evidence in front of the jury: the weapon prosecutors tie to the shooting and writings they say show intent. The partial suppression trims the edges of the search without gutting the case, and it preserves an appellate issue the defense can raise later.