Criminal corpse is on file (10)
I believe the answer is:
procession
'file' is the definition.
(thesaurus)
'criminal corpse is on' is the wordplay.
'criminal' indicates an anagram.
'corpse'+'is'='corpseis'
'corpseis' with letters rearranged gives 'processi'.
'processi'+'on'='PROCESSION'
(Other definitions for procession that I've seen before include "Parade, cavalcade" , "Motorcade" .)