Volume is covered by legal document, as planned (7)
I believe the answer is:
devised
'planned' is the definition.
('devise' can be a synonym of 'plan')
'volume is covered by legal document' is the wordplay.
'volume' becomes 'v'.
'covered by' indicates putting letters inside.
'legal document' becomes 'deed' (deed is a kind of legal document).
'v'+'is'='vis'
'vis' placed inside 'deed' is 'DEVISED'.
'as' is the link.
(Other definitions for devised that I've seen before include "Invented" , "Came up with, a plan say" , "Conceived" .)