Check nothing will get you a ban (4)
I believe the answer is:
veto
'a ban' is the definition.
(veto can mean a ban or prohibition on something)
'check nothing' is the wordplay.
'check' becomes 'vet' (to vet someone is to check their background).
'nothing' becomes 'O' (looks like zero - 0).
'vet'+'o'='VETO'
'will get you' acts as a link.
(Other definitions for veto that I've seen before include "Disallow" , "Ban; refuse to allow" , "A confused vote, altogether negative" , "UN rejection" , "Overrule, forbid" .)