The U.S. Supreme Court case Norfolk Southern Railway Company v. Dedra Shanklin, individually, and as next friend of Jessie Guy Shanklin in 1999 involved a dispute over the adequacy of warning devices at railroad crossings. The plaintiff's husband was killed when his vehicle collided with a train at an intersection equipped with reflectorized crossbuck signs but no automated flashing lights or gates. The plaintiff argued that the railway company was negligent for not installing more advanced warnings despite knowing about the dangerous conditions at this crossing point. However, the court ruled in favor of Norfolk Southern Railway Company based on federal preemption doctrine which states that once Federal Railroad Administration (FRA) funds have been used to install safety devices at a particular crossing under its program to improve rail-highway crossings nationwide, state tort law is preempted from imposing liability for failure to maintain additional safety measures beyond those funded by FRA unless there has been negligence on part of railway company leading to malfunctioning or absence of installed device(s). In this case, since federally-funded crossbucks were present and functioning properly during accident time without any evidence showing negligence by railway company causing their malfunctioning or absence; hence it could not be held liable under state tort law.

In the dissenting opinion for Norfolk Southern Railway Company v. Shanklin, Justice Stevens argued that the majority's decision was inconsistent with previous rulings and federal regulations. He believed that it was inappropriate to rule out state law claims simply because a crossing had received federal funds for safety improvements. Instead, he suggested that such claims should be evaluated on a case-by-case basis to determine if they conflict with specific federal standards or objectives. Furthermore, he pointed out that there were no clear guidelines about what types of safety measures would preclude additional state law requirements - an issue which could lead to confusion and inconsistency in future cases. In his view, this lack of clarity undermined both states' rights and public safety.