Ban, prohibit (6)
I believe the answer is:
forbid
I believe this clue is a double definition.
'ban' is the first definition.
(I know that ban is a more specific form of the action criminalise)
'prohibit' is the second definition.
(I know that prohibit can be written as forbid)
(Other definitions for forbid that I've seen before include "Interdict" , "Deny, prohibit" , "bar" , "Refuse permission, order not to" , "Prohibit, veto" .)