It's a general principle of agency law, but one example would be Skinner v. Railway Labor Executives' Assn., 489 US 602 (1989) involving a drug test performed by ostensibly private railroads, but pursuant to federal regulations. That was considered sufficient government action to implicate the 4th Amendment.
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Is there actually a legal precedent for this?
It's a general principle of agency law, but one example would be Skinner v. Railway Labor Executives' Assn., 489 US 602 (1989) involving a drug test performed by ostensibly private railroads, but pursuant to federal regulations. That was considered sufficient government action to implicate the 4th Amendment.