I emphatically support the protections of the Fourth Amendment, but the Fourth isn't implicated when people *voluntarily* share what they've seen, and it *certainly* isn't implicated in reading what they publicly post to the world. If my garbage isn't private--and SCOTUS has ruled that it isn't--why in the world would I expect that something I post to the internet equivalent of a billboard to be private?What can be done, legally that is? I'm truly curious how something is done without being a police state.
When somebody does something that would make a reasonable person raise an eyebrow and say "that boy just ain't quite right," there's nothing wrong with sniffing around the edges a little bit. Invasive searching, involuntary questioning, coercing people to act as spies, absolutely wrong; but if his neighbor says "y'know, ol' Timmy seems to be buying an awful lot of fertilizer, and his yard just isn't that big," that's not a violation of Timmy's rights or his neighbor's; that's just good police work.