No judge has us over a barrel in the end (7)
I believe the answer is:
refusal
'no' is the definition.
(thesaurus)
'judge has us over a barrel in the end' is the wordplay.
'judge' becomes 'ref' (**).
'has' says to put letters next to each other.
'over' means one lot of letters go next to another.
'in the end' says to take the final letters.
The last letter of 'barrel' is 'l'.
'ref'+'us'+'a'+'l'='REFUSAL'
(Other definitions for refusal that I've seen before include "Rejection; turning-down" , "Dissent" , "fault in the show ring" , "Failure to accept" , "Repudiation" .)