(BALTIMORE) — Deep inside headquarters of the Baltimore Police Department, a vault holds thousands of artifacts from a generation of gun crime and clues to a tide that may be turning. Most of ...

Baltimore Police Commissioner Richard Worley argues that gun parts kits should be treated the same as fully-assembled firearms, subjected to background checks and age limits at the time of sale.

The standard background check for those buying a gun would have turned up red flags, including an illegal weapons violation from four years earlier. But there was no check. The weapon was a so-called ...