I agree with Michael M. that the reporter didn't tell on her source because of her credibility and moral issues of using a 5-year old. Her eagerness and boldness was well depicted at the beginning of the movie. The 5-year old won’t be punished legally but would be destroyed mentally thinking that she caused her mother’s death, which was more what the reporter was trying to protect. Wish the director showed more profound self criticism verbally besides righteousness, which only would make the reporter more a heroine.
Opposite to the wish of the director, I liked the movie until at end when the source was revealed to the audience. Started with using a 5-year old, just not very appealing.