You post what you hear, you take the risk that someone involved in the communications will both be angry, and have lawyers available.
If they choose to bring charges, even if you win eventually, you lose time, court costs, etc.
The law is unclear, in that the law specifically says you may not disclose, but it's been held (and apparently sometimes in court, successfully), that the ECPA, in making it explicitly legal to monitor certain things, also made it legal to disclose them... though it does NOT specifically say that.
See Rose v. United States, 669 F.2d 23, 26 (1st Cir. 1982). The legal prohibition on disclosing intercepted radio transmission was first enacted as Section 305 (later renumbered Section 605) of the Federal Communications Act. "When Congress passed Title III [of the Safe Streets Act], however, it simultaneously amended § 605 to state that § 605 does not apply to communications that may be intercepted and disclosed under Title III by prefacing § 605's prohibition against disclosure with the words "except as authorized by [Title III]".
That's about as explicit as one can get.
In general, Title III puts FM transmissions, not encrypted, by Part 90 licensees on Part 90 frequencies, in the public domain.
The law is pretty clearly delineated in 18 U.S.C.A. section 2511(2)(g):
It shall not be unlawful under this chapter or chapter 121 of this title for any person—
(i) . . .
(ii) to intercept any radio communication which [sic: that] is transmitted—
(I) by any station for the use of the general public, or that relates to ships, aircraft, vehicles, or persons in distress;
(II) by any governmental, law enforcement, civil defense, private land mobile, or public safety communications system, including police and fire, readily accessible to the general public;
(III) by a station operating on an authorized frequency within the bands allocated to the amateur, citizens band, or general mobile radio services; or
(IV) by any marine or aeronautical communications system;