Prevent crime writer dropping The Times (5)
I believe the answer is:
deter
'prevent' is the definition.
(I've seen this in another clue)
'crime writer dropping the times' is the wordplay.
'crime writer' becomes 'dexter' (Colin Dexter).
'dropping' is a deletion indicator.
'the times' becomes 'x' (x resembles the multiplication or times sign).
'dexter' with 'x' taken away is 'DETER'.
(Other definitions for deter that I've seen before include "Warn off" , "Hinder, prevent" , "Daunt" , "Dishearten" , "'Discourage, dissuade (5)'" .)