Dutton toggle caption Dutton First Platoon: A Story of Modern War in the Age of Identity Dominance, by Annie Jacobsen Dutton It's common knowledge that the FBI has a database of people's fingerprints. Many local police have their databases, too. And so, it turns out, does the United States military. American forces have been gathering biometric data on the people they encounter in war zones for years. It's a way to tell the good guys from the bad – though investigative reporter Annie Jacobsen argues it doesn't always work. In a book called First Platoon, Jacobsen follows the lives of Americans told to gather that data in Afghanistan — and she questions what the U.S. government means to do with it all.