What is the meaning of the legal phrase 'Nemo Debet Esse Judex in Propria Sua Causa'?

no one can give what he does not have He who acts through another does the act himself of/on the same subject matter no one should be made a judge in his own cause

no one should be made a judge in his own cause

Nemo Debet Esse Judex in Propria Sua Causa: It means no one should be made a judge in his own cause. It is popularly known as the rule against bias. That is the authority sitting in judgment should be impartial and act without bias. If a judge or adjudicating authority is biased either in favour of one party or against the other, he cannot be expected to do justice in the matter. Such a person is disqualified from adjudicating and since such proceedings stand vitiated, any decision taken by him is liable to be set aside. This basic rule applies to all judicial authorities as well as to all administrative authorities who are required to act judicially or quasi-judicially. The rule is of wide application and means that a judicial or quasi-judicial authority should not only himself not be a party but must also not be interested as a party in the subject matter of the dispute which he has to decide.