Name this logical fallacy.

February 4, 2006 11:27 AM

Can you provide the name and/or good examples of this logical fallacy?

Someone justifies illegal or improper behaviour on the grounds that virtually everybody violates this law in some way, so it should not apply to them.
Example: "I shouldn't be fined for speeding, since virtually everybody exceeds the speed limit without consequence."

posted by weapons-grade pandemonium to writing & language (15 comments total)

Appeal to Common Practice
posted by Espy Gillespie at 11:31 AM on February 4, 2006

I'm a logic newbie, so take what I have to say with a grain of salt...

It's definitely an appeal to common practice, by its definition. You could also argue that it's a red herring, as the fact remains that they broke the law and should be punished; whether other people are punished or not is an irrelevant fact.
posted by charmston at 11:41 AM on February 4, 2006

Closely related is the tu quoque fallacy, which would be "You were speeding." "Well, you were speeding, too!"
posted by ubernostrum at 12:03 PM on February 4, 2006

Good list of, and definition of, logical fallacies here. It relates all the fallacies to baseball, but it's a pretty useful thumbnail of the different types of logical fallacies...
posted by pdb at 12:21 PM on February 4, 2006

It is like appeal to common practice, but with a twist. It has to do with claiming imperfect justice and ignoring degree--justifying extreme behaviour on the basis that lesser behaviour, although still illegal, goes unpunished. It's not quite two wrongs make a right. More like punish everybody or nobody I swear I was reading about this recently, but can't find it again.
posted by weapons-grade pandemonium at 12:43 PM on February 4, 2006

"...since virtually everybody exceeds the speed limit without consequence."

That makes it an appeal to selective enforcement, not just common practice. This police officer thinks it's a good idea. This municipal planning department may not, but admits that it happens despite their intentions. Links via google.

Apparently, being selected for punishment out of a crowd of equally-guilty others can serve as a legal defense only when it can be proved that the criteria for selection are unreasonable in one way or another. That is, they're not supposed to give you a speeding ticket because your car is red or your skin is black, but your steering being wobbly or your tires bald would be a sufficient excuse to single you out for punishment for an actual offense even if those things aren't illegal in themselves. Or something like that.
posted by sfenders at 1:02 PM on February 4, 2006

It's also closely related to the naturalistic fallacy. The examples on the linked page kind of suck.
posted by duck at 1:49 PM on February 4, 2006

If A then B, therefore if B then A.

Also: Your fiscal policy can't be considered because you cheated on your wife.
posted by crapples at 2:04 PM on February 4, 2006

Whoops - Sorry. I misread the question -- thought you were looking for examples of logical fallacies (in general). On review I see that you wanted examples of that specific fallacy.

I'll be quiet now.
posted by crapples at 3:32 PM on February 4, 2006

james frey could defend himself by saying there's lots of memoirs that aren't literally accurate.
posted by alkupe at 3:46 PM on February 4, 2006

At least in California, your example is not always illegal, nor a fallacy. I forget the legal term, something like Natural Speed Limit or somesuch, that states if you are exceeding the speed limit, but moving with the flow of traffic then the actual speed limit is that of the traffic, and you are permitted to drive that speed.
posted by Manjusri at 6:13 PM on February 4, 2006

"But Mom, everybody's getting their fleshy bits pierced!" "If everybody jumped off a cliff, would you do it too?"

It's the lemming lemma.
posted by rob511 at 8:39 PM on February 4, 2006

An officer isn't asking whether everyone else speeds, he caught you speeding and whether you're guilty. It's not logically sound because it completely muddles up the accusation with trivialities. Consider:

"I am arresting you for possession of marijuana."
"But.. I only like bananas!"

The issue isn't whether the arrestee used it, it's possession of it that's the crime. To the arrestee it seems to make sense, but absolutely ignores that actual facts of the arrest. The everyone-else-does-it remark tries to appeal to the emotion rather than the law, and emotion has little to do with it in the first place -- just as whether you prefer bananas to marijuana doesn't matter if you've actually got some in your possession.
posted by vanoakenfold at 6:51 AM on February 5, 2006

See also jury nullification, and the Chewbacca Defense.

I forget the legal term, something like Natural Speed Limit or somesuch

That's probably a confused reading of the 85th percentile rule. A properly signed speed limit backed by legislation should not be susceptible to this sort of defense.

It is unfortunate -- and telling -- that the Appeal to Common Practice is being used by the sitting Attorney General of the United States, rather than, for example, a legal argument.
posted by dhartung at 4:41 PM on February 5, 2006

Probably sfenders was closest to answering my question with his selective enforcement link. Lots more interesting links and comments though. Thanks to all.
posted by weapons-grade pandemonium at 6:05 PM on February 5, 2006