Pardoned former partner, Conservative, exploited (7)
I believe the answer is:
excused
'pardoned' is the definition.
('excuse' can be a synonym of 'pardon')
'former partner conservative exploited' is the wordplay.
'former partner' becomes 'ex' (an ex-partner).
'conservative' becomes 'C' (UK political abbreviation).
'exploited' becomes 'used' (synonyms).
'ex'+'c'+'used'='EXCUSED'
(Other definitions for excused that I've seen before include "Forgiven" , "Overlooked offence or released from duty" , "Made allowances for" , "Exempted from task" , "Granted exemption" .)