The commission is declared to be an instrumentality of the party States exercising a governmental function. It shall enjoy the sovereign immunity of the party States and may not be sued in any court or tribunal whatsoever; nor shall it have the power to pledge the credit of the party States or any of them, or to impose any liability upon them, or any one of them, directly or indirectly, either by tort, contract or otherwise.
N.J.S. § 32:22B-11