As a teenager, Noura Jackson was convicted of killing her mother, and then spent nine years in prison. But from the start, prosecutors possessed a document that could have set her free. Why the omission of evidence, despite its life-altering consequences, is hard to detect — and rarely punished. Guest: Emily Bazelon, a writer for The New York Times Magazine who has been following Ms. Jackson’s case. For more information on today’s episode, visit nytimes.com/thedaily.