Taken from http://www.shotgunrules.com:
The Theory
The term "Shotgun" refers to the front passenger seat of an automobile. "Calling Shotgun" is the act of claiming the position of Shotgun for one's self. As this position is the most coveted of all positions when riding in a car, the following list of rules has been created to ensure that Shotgun can be acquired in a fair and equitable manner by any passenger of an automobile.
The History
The history of calling "Shotgun" goes back to the days of covered wagons and the Wild West. On a trip across the plains, the driver of a wagon would hold the reins of his horse team and concentrate on driving. This left him and the occupants of his wagon susceptible to sneak attacks from bandits and thieves. To avoid this atrocious circumstance it became necessary for one person to sit next to the driver with a shotgun and fend off the enemy.
Defending against bandits is no longer the priority of Shotgun however, but it has evolved into a pre-driving ritual that is experienced before almost every car ride across America and even the world. Because of the obvious evolution that has already occurred with Shotgun, we ask you to consider Shotgun as a living entity and be aware that it is always changing for the better good of society.
The Rules
The following rules have been created through many years of exploring the ritual of Shotgun and are designed with the idea of fairness to all as the main priority. They are also the most complete and comprehensive listing of Shotgun rules available today.
You Must Say The Word "Shotgun"
You must say the word "Shotgun" to stake your claim on Shotgun. This must be done clearly and loud enough so that at least one other to-be occupant of the vehicle can hear you. No variations of this word are acceptable. After you have rightfully called Shotgun, you have exclusive rights to Shotgun for that ride. However, if no one hears you call Shotgun it is still fair game for everyone.
The Deed Must Be Done Before Shotgun May Be Called
For these rules to work properly, it is essential for you to understand and accept the concept of the "Deed". Shotgun may only be called after the "deed is done". Simply stated, the deed is any activity or objective that directly precedes the ride in the automobile. The deed can be anything ranging from a visit at a friend's house, to a shopping trip at the mall, to a visit to the Grand Canyon. We cannot stress how important this is because this establishes a Shotgun-calling time frame that ensures everyone has an equal chance of recognizing when to call Shotgun.
There is no crime greater than calling Shotgun on Monday in reference to the ride to the concert on Friday. Some people choose to play this way, and they are fools.
You Must Be Outside To Call Shotgun
The best way to establish exactly when the deed is done is to define this moment as the instance that you have left the building in which the deed took place. All passengers need not to have exited, but someone must hear you call Shotgun.
Some people choose to use a variation of this rule and require that all occupants be out of the building before Shotgun can be called. This does not work. It leads to everyone calling Shotgun at the same time and often ends in physical violence.
The Barefoot Rule
Since you must be outside to call Shotgun, some people will just grab their shoes, jump outside, and call Shotgun before putting their shoes on. This has been deemed "gaping", and is not a legal procedure. You must have your shoes on, if you choose to wear any, before you may call Shotgun.
The Re-entry Rule
If you call Shotgun and then go back inside for some reason, you must re-call Shotgun after leaving. After you have re-entered the building, Shotgun is once again fair game to all.
When The Deed Is Outdoors
If the deed takes place outdoors, which it often does, the completion of the deed must be agreed upon when Shotgun is called. Any major disputes over the completion of the deed, as with any discrepancy, can be easily settled with a quick round of Rock, Paper, Scissors.
The Line-Of-Sight Rule
In the situation of the deed being a hike or other extensive outdoor activity, you may not call Shotgun until the automobile is within your sight. This rule needs only to be used when the passengers are outside for a long time and have traveled long distances from the car, as with a day of snow skiing.
Miscellaneous 
Hand On Door
Shotgun can no longer be called once someone's hand is holding the shotgun door handle. This officially stakes their claim to Shotgun and calling it at this time is just redundant. This is one scenario where a person does not actually have to say Shotgun to get the seat. This rule's importance is that no one has to be around for you to stake your claim to Shotgun, whereas usually one other would-be occupant must be present for you to call it.
Sit Down
If you manage to sit in Shotgun before anyone has called it, you keep the position even if someone else calls shotgun after you sat down. This is very similar to the Hand on Door rule, where you do not actually have to say Shotgun nor does anyone else have to be present for you to claim it.
The Balk
This rule is applied when you have called Shotgun and are waiting for the doors to be unlocked. If you lift the handle while the doors are being unlocked and therefore cause the Shotgun door to remain locked, then you are "voided" for that ride. At this time Shotgun is available for all of the other passengers to call.
Garages
If you enter a garage that is connected to a house or building without having to go outside, then you may call Shotgun as soon as you enter the room. This only applies to small attached garages. Parking structures and detached garages are always considered as being outdoors, even if they are underground.
Multiple Cars
In the situation where a group of people are travelling in multiple cars, you must specify which car you are calling Shotgun for. For example: if the two drivers are named "Bob" and "Sue", then someone must say "Shotgun Bob" or "Shotgun Sue" depending on which car they would like to ride in.
Shotgun Abandonment
If the Shotgun occupant exits the car to accomplish a deed, Shotgun becomes eligible to the remaining passengers in the other seat(s). Once Shotgun is available, you must call Shotgun before the other occupants. Often times there is discrepancy regarding when Shotgun actually becomes available. Several attempts have been made to clearly define this point, yet no truly fair rule can be applied here. For this reason, one game of Rock, Paper, Scissors is usually the easiest way to solve the problem. Exception: If the Shotgun rider abandoned the seat to do a deed for the driver, i.e. purchasing cigarettes or pumping gas, that person retains Shotgun.
Other Seats
Once the Shotgun seat has been called by someone, the other less prestigious seats in the car may be claimed using the same rules as calling Shotgun. For example: you can say "back-right" or "back-center". In addition, you may also negate calls such as "not back-center" which would put you in any seat except for the back-center.
Remain Seated
If you choose to remain in the automobile while the other passengers accomplish their deed, you may retain full rights to Shotgun. Often times not everyone needs to go inside when completing menial deeds. It can be abused however when a certain person is willing to wait in the car for extensive periods of time in order to retain the rights to Shotgun. This type of person is considered to be a "Shotgun Gaper".
The Shotgun Gaper
Gapers (gay-pers) are people who prioritize Shotgun much more than a normal human being. These people will alter their usual behavior and even undermine their own ethics in order to gain the rights to Shotgun. They do this through legal means such as sprinting for an exit, and therefore they cannot be voided. The term gaper was originally given to Will Henderson who once rode Shotgun for 2 months straight. The advantage to being a Shotgun Gaper, of course, is you always get Shotgun. Being a Shotgun Gaper, however, is frowned upon.
If you know any Gapers and disapprove of their gaping ways, visit our Gaper page. There you will find tips and tactics to help you beat the Gaper at their own game.
Voiding
Whenever you break a Shotgun rule as stated in this guide, you may be voided from receiving Shotgun privileges for that ride. Although somewhat discretionary, voiding automatically applies if you call Shotgun while indoors, or if you do not have your shoes on and call Shotgun, or if you display any other blatant disregard for Shotgun protocol. In circumstances of minor Shotgun rules infractions, voiding may not need to be exercised. Being void only applies for the ride directly after the voiding has occurred and after that ride you may regain full Shotgun privileges. Once someone has been voided, then all of the other passengers are free to once again call Shotgun in the correct manner.
Discrepancies
If a discrepancy ever occurs, and they commonly do, over who rightfully gets Shotgun, it is usually settled with a single game of Rock, Paper, Scissors. A common application of this procedure takes place after two people call Shotgun at the exact same time. Click here to play a game of Rock, Paper, Scissors against the computer. Also consider buying one of our professionally printed rulebooks to help settle disputes on the road.
Special note regarding discrepancies: many people use a "driver override" rule that says the driver of the car settles any discrepancies. The driver override rule also says that a driver has the final say about who gets to ride Shotgun. This version of the rule is very subjective and defeats the purpose of calling Shotgun. Rock, Paper, Scissors is a much more fair and objective way of settling any disputes.
New Rules
Because Shotgun is a living entity and constantly changing, new rules always need to be created. Any group of people is welcome to implement their own rule if the situation arises. A new rule will often be created following a major discrepancy. The important thing to remember about this is that the new rule does not take effect until the next car ride.
Exceptions
Although the Shotgun rules have been created with ultimate fairness in mind, there are situations where exceptions need to be implemented.
Significant Others
This is the most important exception. If a significant other (SO) is included in the group of automobile passengers and this person is the SO or potential SO of the driver, then they get automatic Shotgun privileges.
Multiple Calls
There is a rare exception where more than one person may have rightfully called Shotgun. This happens when multiple groups of people are meeting at a car, and both groups had someone claim Shotgun. If it can not be determined who made the call first, then the only fair way to settle the dispute is with Rock, Paper, Scissors.
Owner-Driver Switch
If someone is driving an automobile other than its owner and the owner becomes a passenger, then the owner automatically gets Shotgun. When applied, this rule shows respect to the owner of the car.
The Long Haul
The rules listed above have been designed around the shorter trip (less than 1 hour). For longer journeys it is best not to use these rules because the incentives to be a gaper are too great. Rather, you should divide Shotgun equally among those who want it.
The Thee Laws of "Radio"
In addition, anyone who gets into my vehicles while I am driving automatically forfeits the privilege of commanding the radio. By radio, I mean any electronic apparatus design to play different media formats to produce and control music in the car.
The Three Laws:1. When in Nelson's car and he's driving, you will not touch his radio or anything controlled by that radio. This includes FM/AM/Satellite radio, iPods or other digital players, CDs, LPs, 8-tracks, or cassettes.
2. If you want to touch the radio, you may ask Nelson if you may exercise limited control over the radio. If he agrees,
then and only then can you touch the radio and only for the suggested action that was granted. Nelson reserves the right to revoke your privilege at any time.
3. If you violate any of these laws while Nelson is driving, Nelson reserves the right to put you out on the street as punishment.
Note: In the event the car is owned by someone else other than Nelson, the rules are then modified to have the owner of the vehicle be the go-to person regarding the 3 Laws. In the event the car is owned by Nelson, however, Nelson has forfeited the right to drive, the current driver is the go-to person regarding the 3 Laws.
I ran into a situation this weekend with someone who insisted on trying to violate the 3 Laws. It made for an interesting time nonetheless as Law 2 came into the picture
I hope to avert any more disagreements in the future by posting the Laws here. Read them and learn.
 | Currently listening :
Light Grenades
By Incubus
Release date: 28 November, 2006 |
. I get really short with them, and with my body language make it very clear that I am annoyed by them. I then get angry at myself for being a dick about it. They have some redeeming values otherwise I wouldn't be around them, but I am at a loss as to how to figure out what about me is making me feel this way. How do you guys deal with it?