Wharton's Law Lexicon, 15th Edition, the word ‘natural justice' has been explained thus
“Natural justice – the aim of the rules of natural justice is to secure justice or to put it negatively to prevent miscarriage of justice. These rules can operate only in areas not covered by any law validly made. In other words they supplant the rules of natural justice which are not embodied rules. What particular rule of natural justice should apply to a certain given case must depend to a great extent on the facts and circumstances of that case, the framework of the law under which the enquiry is held and the constitution of the Tribunal pointed for the purpose,
A.K. Kraipak v. Union of India, AIR 1970 SC 150.