Justify being wrongly severed (7)
I believe the answer is:
deserve
'justify' is the definition.
(I've seen this before)
'wrongly severed' is the wordplay.
'wrongly' indicates anagramming the letters (I've seen this in other clues).
'severed' is an anagram of 'DESERVE'.
'being' is the link.
(Other definitions for deserve that I've seen before include "Warrant" , "Merit (something)" , "Merit, earn" , "Show one is worthy" , "Severed (anag)" .)