Corruption: zero tolerance cases (3)
I believe the answer is:
rot
'corruption' is the definition.
(rot can mean corruption or decay)
'zero tolerance cases' is the wordplay.
'cases' says the answer is hidden in the clue.
'ROT' can be found hidden inside 'zero tolerance'.
(Other definitions for rot that I've seen before include "Balderdash" , "Cobblers" , "Putrefy" , "Corruption" , "Informal nonsense" .)