I'm certain that, legally, it must be possible, lest an entire community become involved in an elaborate cause stalking case and end up in prison.
This website is an abomination, and an extreme invasion of privacy, especially considering how nosy neighbors are. Additionally, information on people who aren't members can be filled in by members.
I registered a fake-ish account, and got a preview of the area around me. I saw a lot of false reports -- massive numbers of break ins, all that -- some of which occurred at the address of the residents I suspect are making the posts.
When I see people from the neighborhood rifling through my mailbox, and everyone seems to know what I'm doing 24/7, and that's nowhere on Facebook, I suspect nextdoor.com.
That's because I know the amount of crap I've been through cannot be law enforcement, if there was any kind of investigation about me, that would have ended three years ago.
This has happened to me at every address in every city I've lived for the past six or seven years, and the same faces appear everywhere.