About to enter English court, Edmond's case is established (7)
I believe the answer is:
erected
'is established' is the definition.
(erect can mean to establish a building)
'about to enter english court edmond's case' is the wordplay.
'about' becomes 're' ('re' means regarding or about).
'to enter' means one lot of letters goes inside another.
'english' becomes 'e' (abbreviation).
'court' becomes 'ct' (abbreviation used in road names).
'case' means to remove the middle letters.
'edmond' with its middle taken out is 'ed'.
'e'+'ct'='ect'
're' going into 'ect' is 'erect'.
'erect'+'ed'='ERECTED'
(Other definitions for erected that I've seen before include "Put up (a building)" , "No Clue" , "Fixed up" , "Constructed, built" , "Set up" .)