Sinquefield began his career with Norfolk Southern in 1985 as a special agent and advanced through a number of positions within the police department.
Sinquefield completed Norfolk Southern' s Executive Development Program conducted at the University of Virginia's Darden School of Business in Charlottesville, Va., and was the first Norfolk Southern police officer to complete the Federal Bureau of Investigation's National Academy in Quantico, Va.
Shackelford joined Southern Railway, a Norfolk Southern predecessor, as a special agent in 1973 and advanced through the department until becoming director police in 2008.
The Norfolk Southern police department is responsible for crime prevention and criminal investigation involving railroad property or interests, protection of high-value shipments, investigation of suspected fraudulent claims against the railroad and other special criminal investigations. The department supports 49 field offices, five special investigation units, three special operations response teams, 12 K-9 units and a police communications center.