If the officer has pulled you over for a valid traffic stop, as with an illegal tint, then the officer can request that you step out of the car.  In fact, many do for safety reasons.  The safety reasons include not standing in the roadway to talk to you-- at the back of the vehicle is much safer.  If there were weapons in the car, having you stand at the back reduces your access to them. If he physically and forcefully removed you from the car, then there are issues with the removal without some exception.  An exception would include there was an active warrant for a violent offense for your arrest or you have previously engaged in comments or actions during the stop that gave the officer have a valid concern for his/her safety.  An officer can only use the amount of force necessary to accomplish his function.