Morse perhaps starts to criticise other detectives' evidence (4)

I believe the answer is:

code

'morse perhaps' is the definition.
(morse is a kind of code)

'starts to criticise other detectives' evidence' is the wordplay.
'starts to' says to take the initial letters.
The initial letters of 'criticise other detectives evidence' is 'CODE'.

(Other definitions for code that I've seen before include "ethical principles?" , "Established standards" , "It may be impossible to read" , "See 12" , "Cryptograph" .)

I've seen this clue in The Independent.

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