Bound to be against punishment (7)
I believe the answer is:
confine
'bound' is the definition.
(I know that bound can be written as confine)
'against punishment' is the wordplay.
'against' becomes 'con' (as in pros and cons, for and against).
'punishment' becomes 'fine' (fine is a kind of punishment).
'con'+'fine'='CONFINE'
'to be' is the link.
(Other definitions for confine that I've seen before include "Shut in" , "pen" , "Imprison" , "Restrict (to an area)" , "Incarcerate" .)