Snapper’s part in shaming a Tory (5)
I believe the answer is:
gator
'snapper's' is the definition.
(short for alligator, an animal which 'snaps')
'part in shaming a tory' is the wordplay.
'part in' says the answer is hidden in the clue.
'GATOR' can be found hidden inside 'shaming a tory'.
(Other definitions for gator that I've seen before include "One taking snaps" , "Short reptile" , "US snapper" , "one snaps in America" , "Informal American term for semi-aquatic reptile" .)