The DNA molecule is elegant, personal, and can give away a lot more secrets than it lets on. Those secrets were exploited by the law enforcement officers who used a DNA testing website to track down alleged Golden State Killer Joseph DeAngelo.
DeAngelo was a police officer and former military man who covered his tracks impeccably for the era. Because the killer had a tactical background, he was nearly uncatchable by the tools that have historically been available to law enforcement. But some major legal and ethical alarm bells went off at the methods that were ultimately used.
In criminal investigations, does the end justify the means? Does that answer change based on the severity of the crime? And what are the ramifications of the 499 people who were closely surveilled without any culpability?