Expert being paid to take the case likely to stir up anger? (11)
I believe the answer is:
provocative
'likely to stir up anger?' is the definition.
(something provocative may cause anger)
'expert being paid to take the case' is the wordplay.
'expert being paid' becomes 'pro' (a paid professional).
'to take' means one lot of letters go next to another.
'the case' becomes 'vocative' (the vocative case in grammar).
'pro'+'vocative'='PROVOCATIVE'
(Other definitions for provocative that I've seen before include "Aggravating" , "Deliberately aimed at causing a strong reaction" , "Deliberately annoying" , "likely to cause annoyance" , "Designed to cause anger or arousal" .)