Journalistic ethics and identifying someone as NOT a confidential source

Suppose seomone produced a news piece based on a “confidential source”, and I somehow became publicly identified as the most probable source of the leak, though I am in fact innocent. I publicly call out for the journalist to clear me.

Does a journalist have any ethical duty to do so?

Then I’m actually brought to trial because it turn out the information was highly classified. I call the jounalist as a defense witness, and simply ask, “Was I the one?” What is the correct response, based on professional ethics?

Assume the journalist has refused to clear me up to now. Everyone agrees the journalist knows who the actual leaker is. I say to the journalist, “If I AM the leaker and you recognize me as such, then I now revoke whatever previous restrictions I placed on you about revealing my identification. Go ahead and tell them all that I made the leak. But if I’m NOT the leaker, you’ll have to maintain your stance against making any comments whatsoever on the identity of the leaker” Would this prove anything to anybody?