Employing or enforcing (8)
I believe the answer is:
applying
I believe this is a double definition.
'employing' is the first definition.
('apply' can be a synonym of 'employ')
'enforcing' is the second definition.
('apply' can be a synonym of 'enforce')
(Other definitions for applying that I've seen before include "Putting into service or asking for a job" , "Employing or enforcing" .)