Do the ends justify the means? Deception in Journalism

In the movie Capote, Truman Capote researches the killing of a family in a small town in Kansas. The police arrest two men, who are placed on death row. Capote interviews one of the men very intensely and becomes very close to him. Capote gains the confidence of the inmate. Capote feels that it is necessary for him to lie to the man to get the story.
At one point in the movie, Capote reads from the book he started writing to a large audience of peple, and says that the book will be called In Cold Blood. The inmate finds out what the book will be titled and becomes upset with Capote. Capote tells the man that whoever relayed the message must have been lying because he would never title the book in such a way as to make the inmate look like a cold-blooded murderer. In fact, capote tells the man he hadn't even started writing the book yet. Capote felt he had to do this to keep the man's trust. But was this ethical?
I think it wasn't ethical for Capote to lie to this man. I think Capote should have attempted being more honest with the inmate. If he wasn't able to get the story that way he probably should have gave up on it, instead of taking advantage of the man. If a journalist was actually in that situation it would be a difficult decision to make.
I think there are instances where deceptive means may be the only option in obtaining a story and it wouldn't be unethical to use them. I heard about a man who painted himslf black to explore racial injustice. He was deceiving people, but I think it was for a good purpose. He could have gone about it differently, but the results would have been different.
There isn't a clear cut answere to deception. It kind of falls in a moral gray area. I think generally deception is unethical and shouldn't be used, but there are some instances where it should be used and may be ethical.