Drink is shown to be the real trouble in court (6)
I believe the answer is:
claret
'drink' is the definition.
(claret is a kind of drink)
'real trouble in court' is the wordplay.
'trouble' indicates anagramming the letters.
'in' means one lot of letters goes inside another.
'court' becomes 'ct' (abbreviation used in road names).
'real' with letters rearranged gives 'lare'.
'lare' placed into 'ct' is 'CLARET'.
'is shown to be the' is the link.
This may not be correct. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for claret that I've seen before include "French wine" , "Purplish-red - blood" , "Red wine from southern France" , "Deep purplish colour" , "Dry red wine of Bordeaux" .)