Container or court proceeding (4)
I believe the answer is:
case
This clue is a double definition.
'container' is the first definition.
(I know that case is a type of receptacle)
'court proceeding' is the second definition.
(I've seen this in another clue)
(Other definitions for case that I've seen before include "Box of twelve bottles of wine" , "Piece of luggage and a lawyer's proceeding" , "Reconnoitre" , "jacket, for example" , "Piece of luggage and a court proceeding" .)