Shotgun riders must keep the driver awake. This means that the Shotgunner must not sleep either. If sleep is needed, the Shotgun rider must move to the back and let someone else take over Shotgun.
4.3.1 If there is no one else available to ride shotgun and you must sleep (trading shifts on a cross-country excursion) you must deal with all necessary distractions the driver may need to stay awake, including but not limit to, loud music, driving with the windows down (no matter how cold), potato chip or sunflower seed bag wrestling, and the necessary punch in the arm to wake up.
4.3.2 Inebriated Shotgunner is an oxymoron. A Shotgunner should be very coherent to help the Driver get everyone safely to their destination. If you are inebriated, you should not take on the role of shotgun. Bonus, if you sit in the back, your driver will look more like an Uber driver than your buddy!