2014 New York Laws
CVP - Civil Practice Law & Rules
Article 9 - (901 - R909) CLASS ACTIONS
901 - Prerequisites to a class action.

  901.  Prerequisites  to a class action. a. One or more members of a
  class may sue or be sued as representative parties on behalf of all if:
1. the class is so numerous  that  joinder  of  all  members,  whether
  otherwise required or permitted, is impracticable;
2.  there  are  questions  of  law  or  fact common to the class which
  predominate over any questions affecting only individual members;
3. the claims or defenses of the representative parties are typical of
  the claims or defenses of the class;
4. the representative parties will fairly and adequately  protect  the
  interests of the class; and
5.  a class action is superior to other available methods for the fair
  and efficient adjudication of the controversy.
b. Unless a statute creating or  imposing  a  penalty,  or  a  minimum
  measure  of  recovery  specifically authorizes the recovery thereof in a
  class action, an action to recover a  penalty,  or  minimum  measure  of
  recovery  created or imposed by statute may not be maintained as a class
  action.