Suspects' excuses
I believe the answer is:
alibis
'suspects' excuses' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for alibis that I've seen before include "They're useful to have if accused of crimes" , "Legal defences of being somewhere else at times of crimes" , "Pleas of being elsewhere at the time of a crime" , "Proofs of absence from the scene of the crime" , "Proofs accused was elsewhere at time of crime" .)