Answer:
   
   Individual beliefs of Rabbis and congregations are personal, and not
   subject to scrutiny by the movement. However, there has been a case
   where a congregation was refused membership in UAHC because they
   removed all references to G-d from their liturgy, and refused to allow
   prayers mentioning G-d to be said in their santuary.
   
   Note that there are rabbis and laypeople in all of the Jewish
   denominations who go through a crisis of faith, have uncertainties
   about the nature of G-d, or who are agnostic or atheist. Faith can not
   be forced. An atheist or agnostic is not someone who thinks "There
   really is a G-d, but I shall not admit it". Rather an atheist or
   agnostic is someone who thinks "I see no evidence for G-d's existence,
   and am certain (or fairly sure) that G-d does not exist." By
   definition, one can never force someone to change their beliefs; that
   can only come about from something internal to that person.
   
   Does Judaism demand that such a person be considered as if they are in
   contempt of Judaism? No. They are only held accountable for their
   actions, for while beliefs are not a matter of choice, actions are.
   The Talmud of the Land of Israel (Talmud Yerushalmi) posits that G-d
   says about them "Would they were to forsake Me, providing that they
   keep My law, for as a result of occupying themselves with it, its
   light will bring them back to the right path" (Tractate Hagigah 1:7,
   76c).