Ridiculous! Hans in red for Jewish judicial council? (9)
I believe the answer is:
sanhedrin
'jewish judicial council?' is the definition.
'ridiculous hans in red' is the wordplay.
'ridiculous' is an anagram indicator.
'hans'+'in'+'red'='hansinred'
'hansinred' anagrammed gives 'SANHEDRIN'.
'for' acts as a link.
(Other definitions for sanhedrin that I've seen before include "Jewish council" , "Ancient court" .)