Scratch Conservative legislation (4)
I believe the answer is:
claw
'scratch' is the definition.
(clawing is a kind of scratching)
'conservative legislation' is the wordplay.
'conservative' becomes 'c' (abbreviation commonly used in UK politics).
'legislation' becomes 'law' (I've seen this before).
'c'+'law'='CLAW'
(Other definitions for claw that I've seen before include "See 3" , "Rake" , "Crab's pincer" , "Scratch - scrape" , "Sharp curved toe of a bird" .)