I read about this too, it's not really a voluntary society in a
   libertarian sense.
   [1]https://www.zerohedge.com/news/2018-07-02/mexican-town-overthrew-the
   ir-local-government-and-things-are-going-great
   From here is linked to a Vice article (and video) about this place:
   [2]https://news.vice.com/en_us/article/gykaq9/a-town-in-mexico-overthre
   w-their-local-government-things-couldnt-be-going-better
   If you watch the vid, one guy works as a professor at a technical
   university, and he gets nominated by his peers and elected to be one of
   the 12 "councilmen" or whatever they call it. It's notable that he
   doesn't have a choice in the matter and has to quit his university job
   for 25% salary as one of the councilmen.
   If your neighbours decide you're standing for election, it doesn't seem
   you have a choice. If they then elect you, you don't have a choice
   either.

   On 3 July 2018 at 18:44, Steven Schear <[3]schear.steve@gmail.com>
   wrote:

   Though some residents complain they are almost required to pay for this
   protection.

   On Tue, Jul 3, 2018, 9:42 AM Zenaan Harkness <[4]zen@freedbms.net>
   wrote:

     A Mexican Town Overthrew Their Local Government And Things Are Going
     Great
     [5]https://www.zerohedge.com/news/2018-07-02/mexican-town-
     overthrew-their-local-government-and-things-are-going-great
      The town of Cherán, Mexico was once plagued…
      Cherán is now run by autonomous groups of armed individuals…
      members of an autonomous militia — guard every entrance to the
     town,
      looking for strangers with contraband…
      “Contraband” would be considered political propaganda posters of
      those who claim the right to rule other human beings.
      …Cherán has achieved something unthinkable in Michoacán: a dramatic
      drop in murder rates, with rates for other serious crimes hovering
      at nearly zero. For those in Mexico, especially in an election year
      marred by wanton political murders, Cherán stands as proof that, in
      the country’s entrenched cycle of violence, the key ingredient to
      that violence is the state.
     In other news:
     Nevada Traffic Deaths Plunge 10% Following Marijuana Legalization
     [6]https://www.zerohedge.com/news/2018-07-02/nevada-
     traffic-deaths-plunge-10-following-marijuana-legalization

References

   1. https://www.zerohedge.com/news/2018-07-02/mexican-town-overthrew-their-local-government-and-things-are-going-great
   2. https://news.vice.com/en_us/article/gykaq9/a-town-in-mexico-overthrew-their-local-government-things-couldnt-be-going-better
   3. mailto:schear.steve@gmail.com
   4. mailto:zen@freedbms.net
   5. https://www.zerohedge.com/news/2018-07-02/mexican-town-overthrew-their-local-government-and-things-are-going-great
   6. https://www.zerohedge.com/news/2018-07-02/nevada-traffic-deaths-plunge-10-following-marijuana-legalization