Clauses appended to legislative bills (6)
I believe the answer is:
riders
'clauses appended to legislative bills' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for riders that I've seen before include "Horse travellers" , "Synge play '. . . . . . to the Sea" , "Travellers on horseback or bicycle" , "Clauses appended to legislative bills" , "Equestrians" .)