I think this changes from country to country. For instance, Gleen Greenwald published illegally obtained conversation in Brazil and had any investigation on how he obtained the data suspended by supreme court. Later was found out that his source was a politician that had interest in the leak, and she also claimed was doing "jornalism work" to avoid legal repercussions. As long you claim to be journalist you have carte blanche.

Not sure if this would play the same in America.