In another case in Yant's book, police witnesses knowingly altered their testimony over a period of months to nail an alleged cop killer. The alterations would have been obvious right away to a thorough journalist. Don't expect a lot of cooperation when investigating the investigators. People in the criminal justice system tend to protect their own. Be skeptical of journalistic accounts.
Reporters often are spoon-fed by prosecutors or, less often, by defense attorneys.
This can lead to selective use of evidence in the journalistic account, conscious or unconscious. That caution holds even for wrongful conviction books. Read Steve Weinberg's account of the Ellen Reasonover story, Railroaded , published in The American Lawyer.