I have to follow law in force (6)
I believe the answer is:
active
'in force' is the definition.
(thesaurus)
'i have to follow law' is the wordplay.
'i have' becomes 'ive'.
'to follow' says to put letters next to each other.
'law' becomes 'act' (I've seen this before).
'ive' put after 'act' is 'ACTIVE'.
(Other definitions for active that I've seen before include "Not passive" , "Vigorously moving" , "In actual operation" , "Moving frequently" , "kind of voice" .)