The killer of a Winchester police officer whose case became a flash point in the debate over Gov. Timothy M. Kaine's views on the death penalty was executed last night by lethal injection after Kaine declined to intervene. Edward N. Bell was ... pronounced dead at the Greensville Correctional Center at 9:11 p.m., said Larry Traylor, a spokesman for the Virginia Department of Corrections. Bell, 44, was convicted in the 1999 killing of Sgt. Ricky L. Timbrook, who was shot while chasing a probation violator. Although capital punishment has been the subject of long-standing debate in Virginia, the case had...