- Ratio Decidendi – The rule of law on which a judicial decision is based. The reason or rationale for the decision by Court.
- Re – In the matter of.
- Reprobata pecunia leberat solventem – Money refused releases the debtor.
- Res – Matter, affair, thing, circumstance.
- Res gestae – Facts surrounding or relevant to a case and admissible as evidence.
- Res integra – A matter untouched by decision. An entire thing; an entirely new or untouched matter.
- Res Ipsa Loquitur – The thing speaks for itself
- Res Judicata – A case which has already been decided.
- Res nulis – Nobody s property.
- Res sub judice – Matter in course of trial.
- Respondeat superior – Let the principal be liable.
- Rex non potest peccare – The King can do no wrong.
- Rex nunquma moritur – The King never dies.
- Rex quod injustum est facere non potest – The King cannot do what is unjust.
