Her action criminal, she’s in solitary (9)
I believe the answer is:
anchorite
'she's in solitary' is the definition.
(an anchorite is a religious recluse)
'her action criminal' is the wordplay.
'criminal' indicates an anagram.
'her'+'action'='heraction'
'heraction' is an anagram of 'ANCHORITE'.
(Other definitions for anchorite that I've seen before include "A solitary person" , "Loner" , "Religious recluse (hist.)" , "Hermit or religious recluse" , "Holy recluse" .)