Topeka Police Lt. Jack Mackey, left, and Jennifer Walker light candles in honor of two officers killed in the line of duty in Topeka, Kan., Monday, Dec. 17, 2012. A man with a history o

 

              Topeka Police Lt. Jack Mackey, left, and Jennifer Walker light candles in honor of two officers killed in the line of duty in Topeka, Kan., Monday, Dec. 17, 2012. A man with a history o
Topeka Police Lt. Jack Mackey, left, and Jennifer Walker light candles in honor of two officers killed in the line of duty in Topeka, Kan., Monday, Dec. 17, 2012. A man with a history of theft and weapons convictions gunned down two police officers investigating possible drug activity in a Kansas grocery parking lot, and was later killed after an armed standoff, authorities said Monday. (AP Photo/Orlin Wagner)