By Kristina Rex

ROCKLAND (CBS) – How does a robbery suspect successfully steal a police cruiser near the scene of the crime? That’s what investigators say Eric Leach did before leading them on a chase through six South Shore communities. The chase ultimately ended after police shot and killed the suspect when he exited the car brandishing a police rifle, according to investigators.

“Does it mean that somebody did something wrong? Not necessarily,” WBZ Security Analyst and former Boston Police Commissioner Ed Davis said.

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A Rockland police officer left his cruiser unlocked with the keys inside as he responded to a call, which allowed Leach to enter the vehicle. The Rockland police chief said he doesn’t blame the officer, and Ed Davis explained to WBZ that it’s a natural error.

“You get a call that there’s an armed robbery, and you race to the scene. You’re not thinking about the security of the vehicle, you’re thinking about the safety of the people,” Davis explained.

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There are mechanisms called kill switches used in some police cars to make them impossible to steal, Davis explained. “Basically every time you put the car in gear you have to press a secret button for the car to move and if you don’t do that the vehicle will stall out,” he said.

The technology is expensive and not widely used, and conversations about kill switches in police vehicles usually arise after situations like the one in Rockland on Friday, Davis explained, but then interest tends to die out as time passes. “I think they’re a great idea,” he said. “And if you can put them into every police cruiser that would be a good thing.”

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The entire incident on Friday is being investigated by the Norfolk County District Attorney’s office, as is protocol whenever police use deadly force.

Kristina Rex