"There’s the kind of boneheaded explanation, which is that a lot of people with PhDs are stupid..."

"... and like many stupid people, they associate complexity with intelligence. And therefore they get brainwashed into making their stuff more complicated than it needs to be," said David Foster Wallace in an old interview.

I think the smarter thing to say is that in many tight, insular communities—where membership is partly based on intelligence, proficiency and being able to speak the language of the discipline—pieces of writing become as much or more about presenting one’s own qualifications for inclusion in the group than transmission of meaning. And that’s how in disciplines like academia—or, I’ve read some really good legal prose, but when it’s really, really horrible (IRS Code stuff)—I think that very often it stems from insecurity and that people feel that unless they can mimic the particular jargon and style of their peers, they won’t be taken seriously and their ideas won’t be taken seriously. It’s a guess.

More of that sort of thing in "Quack This Way: David Foster Wallace & Bryan A. Garner Talk Language and Writing," a newly published book.

Judicial opinions are "poorly written, legalese-riddled," and "read like over-the-top Marx Brothers parodies of stiffness and hyperformality."

Says Bryan Garner, trying to figure out why lawyers write so badly.

The poor lawyers! They are trying to sound like the lawyers who were trying to sound like lawyers who were trying to sound like lawyers who were... etc.

The stakes are high and the desire to sound professional and learned overcomes a native speaker's capacity for natural speech.

But there's also the problem that the arguments judges and lawyers are putting together are full of gaps. Clear speech would make that obvious.