... issue against party helping (13)
I believe the answer is:
consideration
'issue' is the definition.
(an issue that must be considered)
'against party helping' is the wordplay.
'against' becomes 'con' (as in pros and cons, for and against).
'party' becomes 'side' (eg a side or party in a contract).
'helping' becomes 'ration' (a ration is a serving or helping).
'con'+'side'+'ration'='CONSIDERATION'
(Other definitions for consideration that I've seen before include "Study" , "Thoughtfulness - relevant factor" , "factor to be borne in mind" , "Bearing in mind - payment" , "Kindness" .)