Force politician into clumsy lie (5)
I believe the answer is:
impel
'force' is the definition.
(I know that force can be written as impel)
'politician into clumsy lie' is the wordplay.
'politician' becomes 'MP' (Member of Parliament).
'into' is an insertion indicator.
'clumsy' indicates an anagram.
'lie' with letters rearranged gives 'iel'.
'mp' inserted into 'iel' is 'IMPEL'.
(Other definitions for impel that I've seen before include "Urge forward - push" , "Urge or force to action" , "Urge forward, drive" , "Goad" , "Motivate" .)