Branch Indy news supremo protected (8)
I believe the answer is:
armoured
'protected' is the definition.
(I've seen this before)
'branch indy news supremo' is the wordplay.
'branch' becomes 'arm' (synonyms).
'indy' becomes 'our' (I can't explain this - if you can you should believe this answer much more).
'news supremo' becomes 'ed' (editor, newspaper boss).
'arm'+'our'+'ed'='ARMOURED'
Can you help me to learn more?
(Other definitions for armoured that I've seen before include "Having protective covering" , "type of brigade" , "bullet-proof?" , "Well protected" , "protected against attack?" .)