Defence of the absent (5)

I believe the answer is:

alibi

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'defence' is the definition.
(defence given to police by a suspect)

I don't understand the remainder of the clue.

(Other definitions for alibi that I've seen before include "Evidence of (or excuse for) being somewhere else at the time" , "It shows one wasn't at crime scene" , "Pretext; court excuse" , ""suspect's story"" , "Defence against accusation - was somewhere else" .)

I've seen this clue in The Globe and Mail.

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