For Black drivers, a police officer's first 45 words are a portent of what's to come

Scientists are studying police camera footage to understand why some car stops of Black men escalate and others don't. (Hill Street Studios/Getty Images)

When a police officer stops a Black driver, the first 45 words said by that officer hold important clues about how their encounter is likely to go.

Car stops that result in a search, handcuffing, or arrest are nearly three times more likely to begin with the police officer issuing a command, such as "Keep your hands on the wheel" or "Turn the car off."