PHILADELPHIA (AP) — Authorities say the criminal history of a man suspected of barricading himself inside a Philadelphia rowhome should have prevented him from legally owning the firepower he used to wound six police officers in a standoff that carried deep into the night. Maurice Hill, who authorities say had at least a semi-automatic rifle and a handgun when he opened fire on officers Wednesday, has on his record arrests in Philadelphia and adjacent Delaware County between 2001 and 2012.