Works to erase top criminal (8)
I believe the answer is:
operates
'works' is the definition.
('operate' can be a synonym of 'work')
'erase top criminal' is the wordplay.
'criminal' indicates an anagram.
'erase'+'top'='erasetop'
'erasetop' is an anagram of 'OPERATES'.
'to' acts as a link.
(Other definitions for operates that I've seen before include "Performs, surgery perhaps" , "Works" , "[TREAT] s with a knife" , "Performs sugery" , "Functions" .)