Untouchable carcass not to be moved (10)
I believe the answer is:
sacrosanct
'untouchable' is the definition.
(both can mean infallible or unimpeachable)
'carcass not to be moved' is the wordplay.
'to be moved' is an anagram indicator.
'carcass'+'not'='carcassnot'
'carcassnot' with letters rearranged gives 'SACROSANCT'.
(Other definitions for sacrosanct that I've seen before include "above criticism" , "Too important to touch" , "Unchallengeable" , "Too valuable to be changed" , "Co-stars can (anag.)" .)