By IRWIN SPEIZER, Staff Writer Attorney General Roy Cooper said Monday that state investigators have turned up credible evidence of possible misconduct by Division of Motor Vehicle officials in Western North Carolina, and he called for help from federal prosecutors in pursuing the case. "We ... have gathered information that leads us to believe that the public duties of some members of the state Division of Motor Vehicles may have been compromised," Cooper said at a news conference in Asheville. Cooper said the State Bureau of Investigation is probing allegations that some DMV officers have misled investigators; mishandled private...