Peer in uniform (5)
I believe the answer is:
This clue is a double definition.
'peer' is the first definition.
('equal' can be a synonym of 'peer')
'uniform' is the second definition.
'in' acts as a link.
(Other definitions for equal that I've seen before include "Commensurate" , "On a par" , "Match; peer" , "Uniform" , "Peer; evenly balanced" .)