Nemo judex in sua causa - "No one shall be a judge in his own case." Prevents conflict of interest in courts. Often invoked when there is really no conflict, but when there is even the appearance of one.⏎
Nemo debet esse iudex in propria - "No one shall be a judge in his own case." In the past it was thought that it included just two rules namely (1) nemo debet esse judex in propria causa (no one shall be a judge in his own case).⏎
Nemo dat quod non habet - [6] The basic rule that a person who does not own property (e.g. a thief) cannot confer it on another except with the true owner's authority (i.e. as his agent). Exceptions to this rule include sales under statutory powers, and cases where the doctrine of estoppel prevents a legal owner from denying a seller's right to sell.⏎
Nemo auditur propriam turpitudinem allegans - "No one can be heard, who invokes his own guilt." Nobody can bring a case that stems from their own illegal act.⏎
Nemo ius ignoratur censetur - "Not knowing the law is harmful." Everyone should know the law. This is used in European Law-countries with a history of Roman law, the 'sentence' was first made by Aristotle.⏎