“22. The two main principles of natural justice “audi alteram partem” and “nemo debet judex in causa sua” which may be said to involve conferral of a right to be heard before being condemned and the right to an impartial unbiased tribunal. These rights are given for the advancement of justice and promotion of fair play in action. They apply to judicial, quasi judicial and administrative action. It is well settled that these rights can be waived, vide Manak Lal and P.D.Dinkaran (supra).After all, if a person does not want to be heard or does not care if a biased tribunal judges him, there is nothing in the law which prevents him from waiving the rights. This position is firmly established in the decided cases. In a case concerning audi alteram partem a man may well say that he does not want a show cause notice or charges framed against him, or to file a reply to a show cause notice or charges, or that he does not want to be heard or to cross examine witnesses deposing against him. He may keep silent and simply wait for the decision to come. That is because this rule of natural justice exists so that no man may be condemned unheard and must have a reasonable opportunity to defend himself. He may not insist on the right or avail of the right, if opportunity is given and waive it. Such waiver is embedded in the body of law relating to audi alteram partem. In a case concerning nemo debet judex in cause sua in relation