The alleged criminal is, to a certain measure, hardened (7)
I believe the answer is:
accused
'the alleged criminal' is the definition.
The definition and answer can be both people as well as being singular nouns.
Perhaps there's an association between them I don't understand?
'a certain measure hardened' is the wordplay.
I cannot quite understand how this works, but
'a' is within the answer.
'measure' could be 'cc' (cc is a kind of measure) and 'cc' is located in the answer.
The remaining letters 'used' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'is to' is the link.
Can you help me to learn more?
(Other definitions for accused that I've seen before include "Incriminated" , "One tried" , "Defendant in a criminal proceeding" , "He who stands in the dock" , "Indicted" .)