Investigators have long relied on science to help solve crimes, from fingerprint and blood splatter analysis to the psychology of criminal minds. But not every investigative technique rests on solid scientific ground. On this episode, how science is used in criminal investigations, and what happens when these methods aren’t as reliable as we might think.

For years in Hollywood, a kind of mythology has been growing around a specific kind of investigator: FBI behavioral analysts, better known as criminal profilers — agents specially trained in psychology to help decode the minds of serial offenders. In TV shows and movies, they’re shown making brilliant, almost miraculous, connections that ultimately help catch the bad guy. But how accurate are these depictions? Pulse reporter Liz Tung explores the history of criminal profiling, how it works, and what’s behind longstanding criticisms of its methods.
In 2004, the FBI was called in to assist on an investigation into a series of terrorist train bombings in Madrid. The agency connected the fingerprints gathered to a lawyer in Oregon, ultimately arresting him. There was just one problem: They’d nabbed the wrong guy. The attorney was ultimately released and received a settlement, but the fallout wasn’t over. Pulse reporter Alan Yu explores how the blunder led to efforts to create standards for evidence collection.
Jens Ludwig, director of the University of Chicago’s Crime Lab, was taking his dog for a walk, when an unleashed dog came charging towards him. Ludwig started screaming at the dog's owner, his neighbor - the conflict was broken up by a campus security guard. The incident left Ludwig shaken — how did he spiral into such sudden, almost uncontrollable, rage? And what did it say about the deadliest manifestation of such rage — American gun violence? We talk with Ludwig about what his exploration turned up, from how our brains switch from rational to enraged, to what causes eruptions of gun violence — and what strategies could help stop it. Ludwig's new book is “Unforgiving Places: The Unexpected Origins of American Gun Violence.”

How Reliable Is Forensic Science? The Truth About Criminal Profiling and Investigations

The Pulse

How Reliable Is Forensic Science? The Truth About Criminal Profiling and Investigations