Explanation
Audi Alteram Partem in Latin means "listen to the other side", or "let the other side be heard as well". It is the principle that no person should be judged without a fair hearing in which each party is given the opportunity to respond to the evidence against them.
Autrefois acquit means he has already been acquitted and Autrefois convict means he has already been convicted. In both cases, the person pleads immunity from being tried again.