Aliter, in loco alio — Anglice desiderandum furi (5)
I believe the answer is:
alibi
(Other definitions for alibi that I've seen before include "Proof of not being at the scene of the crime" , "Defence that one was somewhere else at the time of a crime" , "Legal defence, plea" , "Court evidence showing one was elsewhere" , "I bail (anag.)" .)