Back in Parliament, sense rampant confusion (5,4)
I believe the answer is:
mares nest
'confusion' is the definition.
(I've seen this before)
'back in parliament sense rampant' is the wordplay.
'back' says the letters should be written backwards.
'in' says the answer is hidden in the clue.
'tsenseram' is hidden in the letters of 'parliament sense rampant'.
'tsenseram' reversed gives 'MARES-NEST'.
(Other definitions for mares nest that I've seen before include "Chaotic situation" , "muddle" , "Complex and difficult situation" , "confused situation" , "confusion" .)