[El Gato]

I could see it as being a standard-size shotgun, the sort that's locked upright to the dash.

Try putting your shotgun in the same position in your full sized car. Bet it hits the windshield. Most of those have 14" barrels. Very few have folding or collapsible stocks. That's the advantage of a short barrel, it's "handier", especially in a confined space like a vehicle, and is also handier in many situations where a longer barrel would sort of get in the way.

[Stoat]

I could see it as being a standard-size shotgun, the sort that's locked upright to the dash.

Try putting your shotgun in the same position in your full sized car. Bet it hits the windshield. Most of those have 14" barrels. Very few have folding or collapsible stocks. That's the advantage of a short barrel, it's "handier", especially in a confined space like a vehicle, and is also handier in many situations where a longer barrel would sort of get in the way.

By "Standard size" I meant "the standard size that's carried on a typical police cruiser".....I 'm aware of the benefits of a shorter barrel of course, but I confess I hadn't checked on what the typical cruiser carries in the way of barrel length versus what's available to the public.  I thought that most carried an off-the-shelf Remington 870 or a standard Mossberg, but if they are shorter than what's available to the public then that's something new for me today.   :-)

I could see it as being a standard-size shotgun, the sort that's locked upright to the dash.

Try putting your shotgun in the same position in your full sized car. Bet it hits the windshield. Most of those have 14" barrels. Very few have folding or collapsible stocks. That's the advantage of a short barrel, it's "handier", especially in a confined space like a vehicle, and is also handier in many situations where a longer barrel would sort of get in the way.