Send down report to the capital (4,2)
I believe the answer is:
bang up
'send down' is the definition.
(both can mean to send to prison)
'report to the capital' is the wordplay.
'report' becomes 'bang' (I've seen this before).
'to the capital' becomes 'up' (as in going 'up' to London).
'bang'+'up'='BANG-UP'
(Other definitions for bang up that I've seen before include "Make prisoner" , "put away" , "Imprison" , "put in cell" , "Pub nag (anag.)" .)