Just drive away!!
The e-mail was basically a warning for people to beware of paper on the back window of their vehicles, because it's a new way to do carjackings. Apparently carjackers are sticking the paper on the back window to obstruct the view of the driver. So when the driver gets into their car and they look into the rear view mirror to back out of their parking space, they notice the paper. They then shift into park, unlock their doors and jump out of their car to remove the paper that is obstructing their view. When they reach the back of their car, that is when the carjackers appear out of nowhere, jump into their car and take off. Plus, a woman would typically leave her purse in the car - making the incident both a carjacking and purse snatching in one. So now the carjacker has their car, home address, their money and keys. Basically your home and your whole identity are now compromised.
Now, whether this is true or not, it sure did make me think about the potential for it happening to me. However, the e-mail said it came from the office of the attorney general. My best advice would be to ignore the paper and just get into the car and drive away. You can always remove the paper later. If you back into another car, your insurance company will be there - that's not just All State's stand.