Prior tempore potior iure - "Earlier in time, stronger in law". A legal principle that older laws take precedence over newer ones. Another name for this principle is lex posterior.⏎
Nulla poena sine lege or nullum crimen, nulla poena sine praevia lege poenali - "No penalty without law" or "no crime, no punishment without a previous penal law". (1) One cannot be prosecuted for doing something that is not prohibited by law. (2) One cannot be prosecuted for doing something that was not prohibited by law at the time and place it was committed, notwithstanding laws made since that time. A form of prohibition on retroactive laws.⏎
Prout patet per recordum - "As appears in the record." Used to cite something that has already been admitted into the record. It was frequently used in pleadings, generally abbreviated "prout &c.", to indicate that a fact was supported by documentary evidence. Failure to use this phrase correctly could be a fatal defect and so cause a case to fail.[7]⏎
Probatio vincit praesumptionem - Proof overcomes presumption.⏎
Pacta sunt servanda - Agreements must be kept. Contracts are the law or contracts establish obligations (between those who sign them).⏎