What's the best way to stop a fleeing car?

What's the best way to stop a fleeing car?

What's the best way to stop a fleeing car?

Answers to your questions about the news.
Oct. 6 2010 5:26 PM

Pull Over! I Said, Pull Over!

What's the best way to stop a fleeing car?

Car chase. Click image to expand.
How do police stop cars in a chase?

A good Samaritan rescued an 8-year-old girl from a kidnapper in California on Tuesday. Victor Perez, who had seen an Amber Alert identifying the suspect's truck, spotted the vehicle from his car and chased after it. After Perez tried cutting off the truck a few times, the abductor gave up and pushed the girl out into the street. What's the best way to stop a fleeing car?

Give it a nudge from the side. The go-to police tactic for ending a car chase is known as the "pursuit intervention technique" or "tactical vehicle intervention". The officer pulls up alongside the perp and then steers his front bumper into the suspect's car along the side and near the back, just behind one of its rear wheels. Because most cars are front-heavy, the tap sends the vehicle into a spin, rotating around the engine. If any of this sounds familiar, it's probably because the move was pioneered by race car drivers. About 90 percent of the time, the spin causes the engine to stall. It's also easier to apprehend a dizzy and disoriented driver.


While the actual execution isn't particularly difficult, the maneuver can be deadly if employed under the wrong conditions. It only works within a certain speed range: Perform it while going less than 35 mph and the fleeing car won't spin but will tilt slightly; do it at very high speeds (above 100 mph), and the other car might flip up into the air. The road surface must be completely flat, and there shouldn't be a curb. Any bump could send the wheels off the ground, and the car could land anywhere. Obviously, there shouldn't be other vehicles in the vicinity. Because of these dangers, police strongly advise civilians not to attempt the maneuver. Even if you're sure you've got a deadly criminal in your sights, just follow behind at a safe distance and call in police backup.

The pursuit intervention technique is probably the most common option these days, but there are others. If given the chance, police officers might place rows of nails called stop sticks in the path of a fleeing car. Deflated tires turn a high-speed chase into a more leisurely affair. Most of the time, the suspect abandons his car and takes off running. Rolling road blocks—surrounding the suspect with two or three police cruisers and steering him off the road—is another way to go, although it puts the officers' cars at risk of being rammed.

Police do engage in their own vehicular ramming—that's the official law-enforcement term—but only under special circumstances. Unlike a little nudge in the rear quarter, ramming is considered a deadly force tactic, and can be used only when the suspect presents a serious danger to the community. When forced to ram, police aim for the engine or the trunk of the car to minimize the chance of killing the suspect.

Shooting is even less common. Some police departments prohibit officers from firing at cars to stop them, while others limit it to the most extreme situations. Cops who try this should aim for the tires, but such efforts are rarely successful.

Police pursuit strategies are in constant flux. Just a few years ago, the conventional wisdom was to tail suspects indefinitely, waiting for them to stop, run out of gas, or make a dumb mistake like driving down a dead-end street. But some have questioned that technique, given that more than 300 people die every year in police-pursuit crashes, with one-third of that number being innocent bystanders. Today, most police departments tell their troops that, if a chase is necessary, it should be ended as quickly as possible on the officer's terms. Still, many departments lack the equipment and training to do this safely, and annual fatalities have changed very little in the last decade.

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Explainer thanks Captain Travis Yates of PoliceDriving.com.

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Brian Palmer covers science and medicine for Slate.