Section 21. Parties to the suit

(l) A suit under section 20 shall ordinarily be brought against the officer or authority charged with the realization of the public demand: Provided that where the suit is brought under clause (b) or clause (c) of subsection (2) of the said section, the Collector shall also be made a party thereto. (2) The [State Government] shall not be made a party to any suit under section 20 unless the public demand was due to the [State Government].