Scrutineer condemned Remain after European vote (8)
I believe the answer is:
examiner
'scrutineer' is the definition.
(thesaurus)
'condemned remain after european vote' is the wordplay.
'condemned' is an anagram indicator.
'after' says to put letters next to each other.
'european' becomes 'e' (abbreviation e.g. EU).
'vote' becomes 'x' (how votes are marked).
'remain' anagrammed gives 'aminer'.
'e'+'x'='ex'
'aminer' after 'ex' is 'EXAMINER'.
(Other definitions for examiner that I've seen before include "Who judges" , "One administering test" , "Tester of knowledge" , "Person testing" , "He gives you paper" .)