Plaintiffs were police officers who had what they thought was a private conversation, but, due to a radio malfunction, it was transmitted on a channel they didn’t even use and was recorded. The conversation led to their termination. The defendants violated no reasonable expectation of privacy in the use of the call because they had no subjective expectation in the use of public property under these circumstance. Lawlor v. Metro. Water Reclamation Dist. of Greater Chicago, 2020 U.S. Dist. LEXIS 41984 (N.D. Ill. Mar. 11, 2020):
Plaintiffs allege that, on the night that their conversation was inadvertently intercepted and recorded, they were on duty at the MWRD’s water treatment plant in Stickney, Illinois.  at ¶ 45. In an attempt to establish that they had a reasonable expectation of privacy, Plaintiffs allege that they were “[b]ehind a closed door in a break room with a lock in a secluded area” while working on the “sparsely manned night shift.” Id. at ¶ 1. However, Plaintiffs do not allege that this “break room” was given to them by the MWRD for their “exclusive use” or that no one else had access to the room (rather than that it was unlikely anyone else would access the room). Plock, 545 F. Supp. 2d at 757. In fact, it was a secret room hidden from MWRD supervisors, and Plaintiff Lawlor named several other employees who had access to the area. [100-1] at 3-4. The surreptitious nature and use of the room distinguish it from true break rooms and areas sanctioned for private use. Cf. Gustafson v. Adkins, 803 F.3d 883, 892 (7th Cir. 2015) (reasonable expectation of privacy in office that female personnel frequently used to change into and out of work uniforms); Richards v. Cty. of Los Angeles, 775 F. Supp. 2d 1176, 1183 (C.D. Cal. 2011) (reasonable expectation of privacy in room where on-duty dispatchers were required to take meal and rest breaks). For these reasons, and those discussed above, even if Plaintiffs had subjective expectations of privacy in their beer-drinking and nap-taking hideout, society does not appear ready to recognize them as objectively reasonable. Thus, the interception of Plaintiffs’ conversation is not a Fourth Amendment search for this reason as well.
Update: See Court To Cops: No Expectation Of Privacy In A ‘Beer-Drinking, Nap-Taking Hideout’ by Tim Cushing.