It is time to stop quivering in our boots in pointless fear of the future and just roll up our sleeves and build it.
- Ray Pierrehumbert

Thursday, July 15, 2010

Climategate and Guantanamo

Still not keeping up... I have a long piece about the burden of proof in climate policy that's been in my mind since 1994 and never been done justice. And now there's this huge Breakthrough Institute push taking shape... all the oh-so-reasonable journos are on board... it's soaked in Broderism... it's going to set back sensible policy another decade. Somebody has to take the literally skeptical literally realist view of this.

Meanwhile Monckton is eagerly grabbing the limelight in blog world for his unseemly attack on John Abraham. They don't make Tories the way they used to, that's for sure. With all due respect to John Abraham and his troubles, though, I wonder if this isn't all coordinated as a timely distraction somehow.

Anyway, I've got to try to get yesterday's main insight on the table before I lose track of it.

Ackerman: "Charlie Savage reports that a federal appeals court has reversed a lower court’s order to free a Yemeni national detained at Guantanamo on suspicion of being a member of al-Qaeda. Here’s his description of the reasoning employed:"
Judge Kessler examined each piece of evidence and found each insufficient to declare him part of Al Qaeda, arguing that flawed accusations cannot be assembled into a persuasive mosaic.

But Judge Randolph criticized that logic as “a fundamental mistake that infected the court’s entire analysis.” He argued that the evidence should be piled together as mutually corroborative because it is probable that a person with many suspicious indicators was part of Al Qaeda.
Spencer Ackerman comments:
From an intelligence perspective, that’s probably persuasive. From a law-enforcement perspective, that’s probable cause. (I guess. I’m not a lawyer.) But for evidence justifying indefinite detention without charge?
I share Ackerman's doubts, though before last November and the "climategate" pseudo-scandal I probably would have gone the other way. (I suppose there's no reason to hope for the present Supreme Court to improve on this. Rather, they will likely align as authoritarians with no thought for principle.)

The issue, fundamentally, is whether a "burden of proof" type decision vs. a "balance of evidence" type decision is indicated in any given case. As a person of Bayesian inclinations, I am generally inclined to a balance of evidence, and am frustrated by demands for "proof", a beast which, it seems to me, exists either only in pure mathematics at best, or possibly not at all.

I think this question has a lot to do with how we respond to climate change and other sustainability questions. I think in matters of strategy, one uses a balance of evidence, but I now see that in matters of justice, one requires near-certainty.

Now, from a Bayesian perspective, twenty independent measures roughly indicating the same thing are collectively compelling even if no single one is. But we can't use that standard in matters of justice, and the so-called "climategate" fiasco shows us why: prosecutors, law enforcers, or plaintiffs can trump up twenty misleading trails of evidence almost as easily as they can put together a single one. In a courtroom, at least there is a balance of effort on each of them. When the battle takes place on the battlefield of public opinion, though, it's asymmetric warfare; the defense has far more work to do than the prosecution. However, even in the courtroom, it's often the case that a committed prosecution has more resources to bring to bear, and the prosecution itself is not always ethical. When your opposition is a motivated person rather than indifferent Nature, the apparent "balance of evidence" can be totally misleading. That is why a burden of proof is necessary in a criminal court.

It may be hard for a scientist to understand the definition of "proof" that is needed in a courtroom; it's certainly difficult for me to understand. But the standard of "beyond reasonable doubt" on any single thread of evidence, rather than "looks fishy" on a bunch of them, is there as a matter of justice.

As Einstein said, the Lord is subtle but He is not malicious. On the other hand, we have this word, "malicious", so it must apply to somebody.

In doing science, we have, in Weiner's sense, an Augustinean devil as opponent; chaos, confusion, disorganization. As such, we can and should operate on the basis of a balance of evidence.

Unfortunately, we confront a culture which expects a Manichaean devil; the opposition is expected to be full of trickery and shabby false promises. Indeed, even our allies within the political culture can also be expected to be full of trickery and shabby false promises, trickery which the opposition will say reflects on ourselves. What the political culture demands is not constant adjustment to prevailing evidence but victory. Evidence is merely among the weaponry, and probably not key among the weapons.

The rational consequence for us scientists is to split the question:
  • decide the science on the basis of a balance of evidence, and then
  • contest policy as a matter of proof, arguing that the balance of evidence is as we state.
(As an aside, Anderegg, Prall et al directly addressed the latter question. Once we get to the latter sphere, we encounter as a matter of course brazen trickery of a sort that as scientists we are careful to avoid and reject within our own sphere. Which is why Anderegg, Prall et al was immediately and vociferously splattered with mud. Fortunately, the attack was so ludicrously overdrawn that the mud didn't stick very well.)

We need to sort out the two types of debate, which for practical purposes (and to keep devils out of the picture) we can call frequentist and Bayesian. It's totally obvious that what we are collectively doing on sustainability questions is excruciatingly far from the Bayesian optimum; that is, the rational expectation is that the result we are apparently headed for is far worse than the best we can do.

How to explain this to the public is stubbornly problematic. I am among those who believe that some of the more committed and sophisticated opposition is quite willfully and deliberately promoting a misunderstanding of the facts.

When they demand "proof" of this or that, they are applying an inappropriate model. We are stuck with a single-subject experiment; there is only one Earth (though there are many models that may or may not be suitable for purpose, they are not perfect) and so the pursuit of "proof" cannot be undertaken in the manner of a clinical trial.

When they engage us under the guise of pursuit of truth, they are exploiting a key weakness - that we are traditionally obliged to take all challenges seriously until proven otherwise. Unfortunately, that obligation needs to be rethought once we are dragged into the world where discourse is replaced by debate and balance of evidence is replaced by "victory". We need to be aware of the tricks.

One of the key tricks of the opposition is a demand for a sort of "proof" that the problem itself cannot yield. As long as legislatures are dominated by lawyers and not scientists, this meta-issue itself requires understanding and careful handling.

7 comments:

You can call me Elle. said...

This may or may not be relevant to what you have posted, but there are many standards of legal "proof," due to the admitted fact that even (some might say especially) in a court case you cannot convince a jury of anything with 100% certitude. From Wikipedia (because I didn't feel like typing it):

"Preponderance of the evidence, also known as balance of probabilities is the standard required in most civil cases. The standard is met if the proposition is more likely to be true than not true. Effectively, the standard is satisfied if there is greater than 50 percent chance that the proposition is true.

Clear and convincing evidence is the higher level of burden of persuasion sometimes employed in both civil and criminal procedure in the United States.
To prove something by "clear and convincing evidence", the party with the burden of proof must convince the trier of fact that it is substantially more likely than not that the thing is in fact true. This is a lesser requirement than "proof beyond a reasonable doubt", which requires that the trier of fact be close to certain of the truth of the matter asserted, but a stricter requirement than proof by "preponderance of the evidence," which merely requires that the matter asserted seem more likely true than not."

The problem is that deniers are gaining traction in their insistence that the science be proven to them Beyond a Reasonable Doubt, like scientists are Perry Mason or something. But the legal system clearly envisions that action must be taken on issues (such as prosecutions, or the assertion of legal rights) even when "proof" in the strictest sense is elusive.

Aside from all this, I think it doesn't matter one way or another because the deniers are not our "jury." A jury is composed of public servants, who take their charge seriously and faithfully perform their duties to the best of their abilities. This has been demonstrated. That's why we use the system. It promotes justice. Deniers are not acting in good faith, they do not want to be convinced by the evidence, therefore they won't be. In voir dire, scientists would kick them off for displaying bias. Unfortunately, we are stuck with them. There has to be some calculation made about who is willing to be convinced by actual evidence and who is just wasting time with bad faith obstructionism.

You can call me Elle. said...
This comment has been removed by a blog administrator.
You can call me Elle. said...
This comment has been removed by a blog administrator.
You can call me Elle. said...

(continued)
The problem is that deniers are gaining traction in their insistence that the science be proven to them Beyond a Reasonable Doubt, like scientists are Perry Mason or something. But the legal system clearly envisions that action must be taken on issues (such as prosecutions, or the assertion of legal rights) even when "proof" in the strictest sense is elusive.

Aside from all this, I think it doesn't matter one way or another because the deniers are not our "jury." A jury is composed of public servants, who take their charge seriously and faithfully perform their duties to the best of their abilities. This has been demonstrated. That's why we use the system. It promotes justice. Deniers are not acting in good faith, they do not want to be convinced by the evidence, therefore they won't be. In voir dire, scientists would kick them off for bias. But we are stuck with them...

You can call me Elle. said...
This comment has been removed by a blog administrator.
Michael Tobis said...

Multiple postings of the same item deleted; no content was removed above.

More glitches at the googleplex, I think.

frank -- Decoding SwiftHack said...

Interesting discussion. In normal jurisprudence, the maxim is to rather let 99 criminals free than to force 1 innocent man to go to jail. Yet when it comes to terrorism, the rules of justice are totally reversed (perhaps because we think that "national security" trumps "justice", as long as the poor guy being affected isn't us).

About prosecution vs. defence: whether each side is the 'prosecution' or the 'defence' depends on the particular claim being made.

Climate inactivists have no problem making sweeping claims like "the Earth will be cooling!" or "Climategate shows clear fraud!" without showing any proof whatsoever, and when they're called on it they just claim that they are "asking questions". In this case, the inactivists will be the prosecution while we're the defence. (I suspect the "Climategate shows fraud! Oh, I was just asking questions" schtick is a ploy to get the strong claims into people's heads without having to subject it to a real challenge -- though, well, I can't say beyond reasonable doubt that this is true.)

If the claim is "is man messing up the planet with greenhouse gas emissions?", the roles in the 'courtroom' are switched: scientists are now the 'prosecution', while the inactivists are the 'defence'.

-- frank