New York Civil Practice Law & Rules Section 401 - Parties.

  401.  Parties.  The  party commencing a special proceeding shall be
  styled the petitioner and any adverse  party  the  respondent.  After  a
  proceeding is commenced, no party shall be joined or interpleaded and no
  third-party  practice  or intervention shall be allowed, except by leave
  of court.

Last modified: February 3, 2019