In the case (Filarsky v. Delia), a firefighter, who was the subject of an internal affairs investigation, sued the city, the fire department, and various individuals under 42 U.S.C. § 1983, alleging that the investigation violated his constitutional rights. (Section 1983 allows suits against those who deprive someone of federal rights “under color” of state law.) The appellate court had ruled that the private attorney was not entitled to immunity. The Supreme Court reversed, concluding that “immunity under § 1983 should not vary depending on whether an individual working for the government does so as a full-time employee, or on some other basis.”
The court surveyed the history of private individuals assisting the government in various functions, noting that “examples of individuals receiving immunity for actions taken while engaged in public service on a temporary or occasional basis are as varied as the reach of government itself.”
The court also noted that denying immunity in such a situation would create a disparity between small municipalities and larger ones with greater resources to hire their own full-time staff:
New York City has a Department of Investigation staffed by full-time public employees who investigate city personnel, and the resources to pay for it. The City of Rialto [the city in this case] has neither, and so must rely on the occasional services of private individuals such as Mr. Filarsky. There is no reason Rialto’s internal affairs investigator should be denied the qualified immunity enjoyed by the ones who work for New York.
