Scarper when constituents complain (4)

I believe the answer is:

carp

'complain' is the definition.
(carp can informally mean to complain or whinge)

'scarper when constituents' is the wordplay.
'constituents' says the answer is hidden in the clue (I've seen 'constituent' mean this).
'CARP' can be found hidden inside 'scarper when'.

(Other definitions for carp that I've seen before include "Fish - grouse" , "Continuously find fault" , "ish" , "Criticise - fish" , "Moan; fish" .)

I've seen this clue in The Irish Times.

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