If the car had points and the points were closed the voltage would be reduced, but if the points were open would not the voltage mesure 12 volts? V=IR The volt meter is a null device, it allows no current so I=0.
I don't know how the electronic ignition behaves when the engine is not running.
Electronic ignitions of the Duraspark type (meaning basically electronic "points replacements" not CD or other fancy-pants stuff) leave the coil saturated with current (eg. "points closed") until the reluctor vanes in the distrib MOVE past the coil. It's magnetic; it doesn't detect position (like points do) but require motion.
Basically it acts like a points car, except the engine never stops with the points open. Makes it much easier to test!