Detective: 'I tape every criminal' (7,3)
I believe the answer is:
private eye
'detective' is the definition.
(private eye is a type of detective)
'i tape every criminal' is the wordplay.
'criminal' is an anagram indicator.
'i'+'tape'+'every'='itapeevery'
'itapeevery' anagrammed gives 'PRIVATE EYE'.
(Other definitions for private eye that I've seen before include "Periodical" , "Freelance detective" , "50 today" , "investigator" , "Investigative satirical magazine" .)