Legislation plays a part (4)
I believe the answer is:
acts
I believe this is a double definition.
'legislation' is the first definition.
(I've seen this before)
'plays a part' is the second definition.
(Other definitions for acts that I've seen before include "spiritual work" , "book form" , "Turns" , "Things done" , "appears (eight in a series may be found)" .)