Now to broader questions:

Is dibs sanctioned? Officially, no. Unofficially, yes. Richie Daley has been famously quoted as saying, "I tell people, if someone spends all that time digging their car out, do not drive in that spot. This is Chicago. Fair warning." The Sun-Times says mayoral candidates Gery Chico, Miguel del Valle, and Rahm Emanuel support the practice, while Carol Moseley Braun waffled. The only one opposing it was William "Dock" Walls, who knows he has no chance of winning and can therefore be bold.

Other towns are stricter, or try to be. Pittsburgh police sternly advise, "Chairs and barriers of any type holding parking spaces on city streets are considered abandoned property and will be removed and discarded." In Boston, car owners are given 48 hours after a storm to remove their "space savers," although how strictly this is enforced is open to doubt. D.C., which is new to the concept of heavy snow, claims it'll fine you.

Are there informal rules for dibs? Some would have you think so. Wikipedia, the noted authority on social mores, lists the "commonly accepted rules of [dibs] etiquette," such as the following:

It is always preferable to help neighbors dig out from heavy snowfall, rather than to claim personal parking spaces with chairs. When chairs are used during snowstorms, their intent must be as a short-term placeholder. A chair cannot be used for longer than the day during which the spot was cleared. It is not a free pass to use the spot indefinitely, especially during longer absences. Parking chairs must be removed as soon as a reasonable number of parking spaces become cleared on a street … Only someone who lives on a street can reserve a parking place. On long streets, the spot should be reasonably close to the home of the person who places it.

And so on. This sort of thing strikes many as hilarious. The Chicagoist comments: "Let's just cite this as the latest example as to why Wikipedia should not be trusted at face value. The chairs currently marking dibs on our block will be on the street through the end of March."

Kass's Law of Dibs is simpler:

The main thing is that in order to claim Dibs, a man must shovel out the space himself, or at least have his wife do it while he relaxes with a soothing beverage so he won't die of a snow-related heart attack. What was shocking and depressing is that Tribune photographers actually found someone trying to claim Dibs even before the snow started falling. And for that, punishment must be swift and sure. It is such a clear violation of the Dibstitution that the person should be banned from exercising Dibs for 10 years.

The other Law, he explained in a 1999 column written not long after he'd introduced the term,  is that dibs doesn't confer property rights in perpetuity:

[W]ith Wednesday's temperatures approaching 50 degrees, it's time, people, to return the ugly dibs claiming chairs to the basement. Dibs are done. Those who persist in claiming dibs are ruining it for everybody … The ancient Bridgeportian texts are clear: "Derain't no snow, soz yain't got dibs no more. Dis aincher praaperdee!"

This column was published January 28; the near-record 1999 storm, which dropped 22 inches of snow on the city, had taken place January 1-3. In other words, dibs was good for a month. Official pronouncements on the subject likewise tend to cut the citizens a lot of slack. In 2010, not an especially epic year for snow, Streets and San declared dibs was done on February 20. In 2009, 33rd Ward Ald. Richard Mell told his constituents to lose the chairs on January 21; the big snow that year happened on January 10-11.

This rankles dibs opponents. Zorn, who has written voluminously on the subject, has proposed two dibs rules. First, you must actually do some shoveling, as opposed to simply driving out of a space that's clear because your car was parked in it, and second, "dibs expires 48 hours after the snow has stopped falling."

Others have taken more proactive steps. Chair-Free Chicago, an antidibs campaign launched this year by Proximity Chicago, a local marketing company, "provides signage that Chicagoans can hang in their neighborhoods to declare chair free zones, as well as fliers that can be placed on rogue items in the street … Fliers range from the apologetically admonishing Minneapolis Mad ('It’s just so gosh darn snowy here in Chicago, if everyone started saving spaces, why, we wouldn’t have anywhere to park!') to the more aggressive New York Mad ('Consider yourself a selfish prick, you selfish prick.')"

Is dibs good or bad? To judge from the philosophical woolgathering, this is one of the great questions of our times. Heavy thinkers have invoked Hobbes and Locke. U. of C. law professor Richard Epstein has written a 37-page treatise on the private-property implications.

Don't worry, I'll spare you. The moral implications of dibsing can be concisely summarized as follows:

1. If you've spent an hour digging out a parking space, absolutely, you've got a claim on it.

2. That doesn't mean you own it till the robins come again.

3. Etiquette my arse — dibsing is mainly an excuse to be a jerk. If you want your own private parking space, move to fricking Winnetka.

4. I'm not saying it ranks up there with the budget crisis. However, if I were mayor, once I got the side streets plowed, the Drive open, and the buses running again, I'd say: OK, muchachos, the crisis is over. Now get your crap off the street.

Postscript: an even better idea

Eric Zorn's column in today's Trib (2-4-2011) about getting together with his neighbors to clear their block, thereby heading off incipient dibsiness, inspires me to make the following proposal. The problem with the dibs vs. anti-dibs debate is that the pro-dibs element has invested some sweat in their spots (excluding the pusballs who put a chair in a spot cleared by somebody else), whereas the anti-dibsters tend to make an ivory tower, for-the-good-of-society argument. Chicago being what it is, this gets you nowhere. The solution, and I'm volunteering the Chair-Free Chicago people to help with this, is as follows:

1. Get together with your neighbors and shovel/snowblow out as many spots as you can, or, if you're really ambitious, the entire block.

2. Put up the following sign next to each spot:

THIS IS A COMMUNITY-CLEARED PARKING SPACE
if you claim dibs on it, don't expect to see your chair again. 

You see what I'm saying? You have to fight muscle with more muscle, preferably a neighborhood's worth. It's the Chicago Way.

The anti-dibs movement, pardon the expression, is snowballing

Eric Zorn, bless his heart, has alerted the masses to the above plan on his blog. Chair-Free Chicago, which isn't taking this — I'm telling you, the puns are sprouting like daisies today — sitting down, is organizing a neighborhood parking-spot-clearing demonstration project. Zorn writes: "Supporters are meeting in front of the Wrigley Building (400-410 N. Michigan Ave.) at noon [as I look at the clock, ten minutes ago] and taking a large van over to Bridgeport to pick a likely street." I'm going to see what I can organize on my street, or to be precise, being the big-picture guy that I am, I'm going to assign Little Ed to do it. More news as it develops.

— Cecil Adams
Photo used with permission of Chair-Free Chicago