(c) The term “confidential communication” includes any communication carried on in circumstances as may reasonably indicate that any party to the communication desires it to be confined to the parties thereto, but excludes a communication made in a public gathering or in any legislative, judicial, executive or administrative proceeding open to the public, or in any other circumstance in which the parties to the communication may reasonably expect that the communication may be overheard or recorded.
'public gathering' is perhaps intentionally ambiguous
the other disjunct: in any legislative, judicial, executive or administrative proceeding open to the public; led me to interpret 'public gathering' as bagley-keene(o) does
> 11122.5. (a) As used in this article, “meeting” includes any congregation of a majority of the
members of a state body at the same time and place to hear, discuss, or deliberate upon any item that
is within the subject matter jurisdiction of the state body to which it pertains.
In many cases federal law trumps state law. State law is likely to not be allowed to hinder a federal investigation. Typically the FBI isn't allowed to record conversations it isn't a party to without a warrant if you have a reasonable expectation of privacy. They are likely going to argue that there is no such expectation of privacy at a public bus stop.
> As the California Supreme Court made clear, federal law (which permits monitoring with the consent of one party) does not preempt more restrictive state eavesdropping laws, even when the monitored communications are interstate. Accordingly, companies that monitor interstate calls for quality control purposes must consult the applicable provisions of state, as well as federal, law. (o)
i feel another commenter, em3rgent0rdr, may have indirectly answered my confusion by stating:
> Even if judges prohibit such evidence on the grounds of it being illegally obtained, you will still find that prosecutors will use that evidence to find other evidence and for constructing a case that doesn't use that illegally obtained evidence. https://en.wikipedia.org/wiki/Parallel_construction (i)
> > As the California Supreme Court made clear, federal law (which permits monitoring with the consent of one party) does not preempt more restrictive state eavesdropping laws, even when the monitored communications are interstate. Accordingly, companies that monitor interstate calls for quality control purposes must consult the applicable provisions of state, as well as federal, law. (o)
This clearly applies to private citizens, but it is less clear that that precedent applies to the FBI.
http://codes.findlaw.com/ca/penal-code/pen-sect-632.html