Obviously in the wrong when returning gifted wine (3-6)
I believe the answer is:
red-handed
'obviously in the wrong' is the definition.
(as in being caught red-handed)
'returning gifted wine' is the wordplay.
I cannot really see how this works, but
'wine' could be 'red' (red wine is an example) and 'red' is found in the answer.
The remaining letters 'handed' is a valid word which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).
'when' acts as a link.
(Other definitions for red-handed that I've seen before include "(Caught) in the act of committing a crime" , "(Taken) in the act" , "Colourfully caught in the act" , "Caught ... ......, apprehended in the act of crime" , "Catch someone thus in the act" .)