This appeal presents the question whether the opening of a locked container, a small safe, to which the police found the key in the course of an inventory search of an automobile, requires suppression of a gun discovered inside the safe. We conclude suppression is required.
This interlocutory appeal by the Commonwealth from a decision of a District Court judge was allowed by a single justice of *402the Supreme Judicial Court, pursuant to Mass.R.Crim.P. 15(b), as appearing in 422 Mass. 1501 (1996), and reported to this court for determination. The background facts as found by the judge after a hearing are as follows.
On February 6, 2007, North Adams police, acting on an arrest warrant, found the defendant seated alone in his car in a parking lot of a Dunkin’ Donuts establishment. After the defendant’s arrest, the police determined that the car, which had been parked in a travel portion of the parking lot, had to be towed.1 An officer began an inventory procedure as required by the policies of both the North Adams police department and the State police.2 After completing examination of the interior, the officer used the defendant’s car keys to open the trunk. Among other items in the trunk, the officer found a small locked safe, six inches by eight inches by fifteen inches. Using a key on the ring of car keys, the officer opened the safe, observing a “blue personal file folder, a watch, two rings and a loaded Raven .25 caliber handgun with a defaced serial number.”
The officer then called a State police sergeant and supervisor of the Berkshire County drug task force, who took photographs of the car and the various items found. The sergeant took the safe and its contents to the North Adams police station and the car was towed. No motor vehicle inventory form was completed and filed.
Discussion. Our review of a motion to suppress requires that we accept the judge’s subsidiary findings which are not clearly erroneous, and that we independently review the ultimate findings and conclusions of law. Commonwealth v. Baptiste, 65 Mass. App. Ct. 511, 514-515 (2006), and cases cited.
In a two-step decision, the judge first concluded that the police lawfully opened the safe, opining that this action was consistent *403with the reasons underlying an inventory search.3 We begin our review mindful that “art. 14 of the [Massachusetts] Declaration of Rights requires the exclusion of evidence seized during an inventory search not conducted pursuant to standard police procedures, which . . . must be in writing.” Commonwealth v. Bishop, 402 Mass. 449, 451 (1988). Because the police in this case had available written policies of the North Adams police department and the State police, we focus our review on what those policies require when a closed, locked container, such as the safe in this case, is found during an inventory search.
With respect to closed areas in vehicles, such as a glove compartment, a trunk, and containers, the pertinent provisions of the Department of State Police, General Order TRF-10 (Jan. 1998) include the following: the glove compartment and trunk should be inventoried “unless they are locked and there is no key available”; “[l]ocked containers should be inventoried as a single unit”; and “[a] search warrant should be obtained before the search of a locked container (or the glove compartment and trunk if they are locked and the officer does not have a key).” See Commonwealth v. Baptiste, supra at 516-517.
The pertinent provisions of the North Adams policy, effective 1999, provide in § IV.B that inventory is to be taken of “unlocked glove/map box areas” and that “the trunk should be unlocked and inventoried”; and in § IV.B.l that if the “glove/map box and/or trunk are locked and the officer does not have a key, these areas should not be inventoried.” Further, § V.A states that *404“[a]ny containers or packages should be inventoried”; and § V.B states that “[cjontents of unlocked containers shall be inventoried separately.”4
While it reasonably may be inferred that both policies permit a locked glove compartment or trunk to be opened if an officer has the key, neither policy indicates whether a locked container may be opened if the officer has a key.
The State police policy distinguishes a locked container from locked glove compartments and trunks by specifically requiring that a locked container be inventoried as a single unit, and that police are required to obtain a search warrant to open it.5 The North Adams policy states that containers and packages should be inventoried, specifically providing that “[cjontents of unlocked containers shall be inventoried separately,” but is silent as to locked containers. We think that such a silence does not permit an inference, as the judge appears to have made, that a locked container may be opened if the police have a key.
Reading the two policies together, we conclude, contrary to the judge’s interpretation, that there is no explicit authority for the police to unlock a closed container and inventory the contents, and that the officer in this case could do no more than inventory a locked container as a single unit. “We have made it clear that, if police open a closed container during an inventory search in the absence of a specific written procedure requiring them to do so, then any evidence they discover in the container must be suppressed.” Commonwealth v. Garcia, 409 Mass. 675, 684-685 (1991). See Commonwealth v. Muckle, 61 Mass. App. Ct. 678, 684 (2004) (police may open closed but unlocked containers where written inventory search so provides).6 For these reasons *405we conclude that the defendant’s motion to suppress should be allowed, and that it is unnecessary to examine in detail the reasons given by the judge in the second step of his decision (see note 3, supra).
Order allowing motion to suppress affirmed.