Coaches and tactical guides generally point out that vehicle stops represent more officer killings than almost any other type of interaction.

Of the some 280 officers killed in service since late 2016, around 60 have died – mostly by gunfire – at the hands of motorists who had been arrested, according to a Times analysis. (About 170 other officers have died in workplace accidents.) But claims of the increased danger ignore the context: Vehicle stops outnumber any other type of police intervention with civilians.

In fact, because police stop so many cars and trucks – tens of millions each year – the chances of an officer being killed at any vehicle stop are less than 1 in 3.6 million, excluding accidents, two studies have shown. At stops for common traffic offenses, the odds are as low as 1 in 6.5 million, according to a 2019 study by Jordan Blair Woods, a professor of law at the University of Arkansas.

“The risk is statistically negligible, but nonetheless it is existentially magnified,” said Mr. Gill, a Salt Lake County district attorney and a strong supporter of increased police accountability.

State laws generally prohibit police from using lethal force unless they reasonably consider it necessary to prevent imminent death or serious injury. Under the pressure of street protests after the 2014 murder of Michael Brown, an unarmed black teenager in Ferguson, Missouri, and the more recent Black Lives Matter marches, many police departments have made de-escalation their watchword. They often advise officers to defuse conflicts with motorists, for example by listening carefully instead of just barking orders.

“The last thing I have to try to do is exercise my authority, like ‘You’re going to do what I tell you to do because I said so,’ said Jon Blum, a former cop who now writes training materials for police services and the International Association of Chiefs of Police. “What the agent has to do is sell the person.”

Departments have increasingly asked officers to let suspected offenders go away and track them down later, avoiding the risk of a potential confrontation or high-speed chase. “You have the license plate of the guy’s car and you know where he lives,” said Scott Bieber, the Walla Walla, Wash., Police chief. “You pick him up in 45 minutes from his home and add an escape charge.”