16. Orders constituting Tribunal or an Appellate Tribunal to be final and not to invalidate its proceedings.

No order of the Central Government appointing any person as [the Presiding Officer of a Tribunal or the Chairperson of an Appellate Tribunal] shall be called in question in any manner, and no act or proceeding before a Tribunal or an Appellate Tribunal shall be called in question in any manner on the ground merely of any defect in the constitution of a Tribunal or an Appellate Tribunal.