Commit a crime? Your Fitbit, key fob or pacemaker could snitch on you.

With no witnesses other than Richard Dabate, detectives turned to the vast array of data and sensors that increasingly surround us. An important bit of evidence came from an unlikely source: the Fitbit tracking Connie's movements. Others from the home's smart alarm systems, Facebook, cellphones, email and a key fob allowed police to re-create a nearly minute-by-minute account of the morning that they said revealed Richard's story was an elaborately staged fiction. Undone by his data, Richard was charged with his wife's murder. He has pleaded not guilty.