Two suspects packing a ghost gun and bags of crack cocaine were arrested after fleeing a Roxbury shooting on a motorcycle Wednesday night — because Boston police pursued and made the collar stick.

The arrest proves what ordinary Americans already know: enforcement works when you let police do their jobs. The 17-year-old suspect was hit with carrying a loaded firearm without a license — his third offense. That's not a policing failure. That's a prosecutor failure. Someone let this teen walk enough times to rack up gun charge number three while still a juvenile.

Boston Police responded to a shooting near Roxbury Street and Malcolm X Boulevard around 8 p.m., the department stated. En route, officers spotted a motorcycle speeding down Shawmut Avenue on the wrong side of the road. The bike crashed into a marked cruiser. The suspects ran. Officers chased them down on foot.

Recovered at the scene: an FN Five-Seven firearm with an obliterated serial number and an empty large-capacity magazine, plus multiple individually packaged bags of crack cocaine. The FN Five-Seven — a pistol originally designed for military use, capable of firing armor-piercing rounds — is a weapon of choice for cartels and traffickers. The obliterated serial number means this gun was almost certainly stolen or illegally trafficked. Nobody with a clean record carries one.

The teen faces a stack of charges: assault and battery with a firearm, assault with a dangerous weapon, carrying a loaded firearm without a license (third offense), possession of ammunition without an FID card, possession of a large-capacity firearm, discharging a firearm within 500 feet of a building, possession with intent to distribute a Class B drug, and resisting arrest. The second suspect, 20-year-old Christopher Amill Jr. of Dorchester, faces assault with a dangerous weapon, carrying a loaded firearm, additional gun charges, and resisting arrest.

The shooting victim was treated for non-life-threatening injuries.

This wasn't the only juvenile gun bust in Roxbury this week, either. Boston Police separately arrested a 15-year-old on a warrant for a September 10 shooting on Dudley Street. Officers recovered a Smith & Wesson Walther P22 with a round in the chamber and ten rounds in a large-capacity magazine. That teen faces charges of assault by means of a dangerous weapon, carrying a firearm without a license, possession of ammunition, and discharging a firearm within 500 feet of a building.

Meanwhile, the violence isn't confined to one city. In Kalamazoo County, Michigan, a shooting Sunday morning left one person dead, according to MLive. A suspect was taken into custody at the scene. The investigation is ongoing.

The Boston Herald covered the Roxbury arrests in a straight police-blotter recitation — facts, charges, move along. What the blotter doesn't ask is the question that matters: why were these suspects — one a repeat firearms offender still underage — on the street to shoot someone in the first place? Boston's progressive prosecutorial regime owns that answer. The police did their job Wednesday night. Someone in a position of authority keeps failing to do theirs.