Suspect’s explanation (5)
I believe the answer is:
alibi
'suspect's explanation' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for alibi that I've seen before include "It shows one wasn't at crime scene" , "Timely plea?" , "Sort of explanation" , "Defence used by an accused person" , "Defence of being elsewhere at time of crime" .)