Pass me a report concealing false accusation (5)
I believe the answer is:
smear
'false accusation' is the definition.
(I've seen this before)
'pass me a report concealing' is the wordplay.
'concealing' indicates a hidden word.
'SMEAR' is hidden in the letters of 'pass me a report'.
(Other definitions for smear that I've seen before include "Badmouth" , "Unwarranted accusation" , "nasty mark" , "allegation" , "Spread dirty substance, try to damage reputation" .)