You may be thinking of Ch’Pok, the Klingon advocate from DS9: “Rules of Engagement”, where they were trying to extradite Worf on the grounds that he had destroyed a civilian transport.

CH'POK: I look forward to fighting on your terms.

SISKO: This is not a fight. It's the search for the truth.

CH'POK: The truth must be won. I'll see you on the battlefield.

And later:

CH'POK: What matters to me is the thrill of the fight, not which side I'm on. And I think we both know the extradition fight is over.