Whether drug and alcohol tests conducted by private railroads under FRA Subpart D constitute government action subject to the Fourth Amendment.
Holding
Yes. Testing performed in reliance on Subpart D sufficiently involves the Government to trigger Fourth Amendment scrutiny.
Reasoning
Subpart C plainly involved government action because it compelled railroads to collect samples. Although Subpart D formally authorized rather than required testing, the Court declined to treat the resulting tests as merely private conduct in a facial challenge to the regulations.
The Government did more than passively permit private testing. Subpart D preempted conflicting state law and collective-bargaining constraints, gave the FRA access to samples and results, prevented railroads from bargaining away their testing authority, and required employees who refused authorized tests to be removed from covered service. These features showed governmental encouragement, endorsement, and participation.