I switched from the left to right lane to make a right turn.The car behind me slowed down as I turned and the car behind him rear ended him. I made my turn and kept driving without incident. Am I legally required to stop and wait for the police?

The scenerio that you describe seems to suggest that you would not be required to stop and wait for the police. As long as you changed lanes without cutting off other motorists, you should be fine. This would be especially true if your car did NOT come in contact with another vehicle. The law presumes that a car that rear-ends another, is at fault. The guy who was rear-ended can file a claim against the car that hit him from behind. For the owner of the car that hit the car behind you to suggest that you caused the car in front of him to slow, and thus was the cause of the accident, would not prevail in a court of law!

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