Tag: Inference

For the Love of Evidence

Over Xmas I listened to Serial, and had a few thoughts about it. Post Xmas I have been catching up on Undisclosed, the pseudo? Spiritual? Something “sequel” to Serial, which follows the exploits of Rabia Chaudry and her friends, as they get to gripes with the case of the murder of Hae Min Lee by Adnan Syed. ((Adnan was accused, and eventually convicted, of the murder of Hae Min Lee back in February, 2000. The evidence used to convict him mostly consisted of a congruence between the sole key witness in the case, Jay Wilds, and a series of cellphone pings which placed Adnan in the vicinity of where Hae Min Lee’s body was buried on the day it was alleged she was murdered.))

Both Serial and Undisclosed are interested in their use of evidence. Serial takes the journalistic avenue of searching for the “smoking gun”, which will either show Adnan to be clearly innocent or guilty. Undisclosed takes the more lawyerly approach of trying to show that the inferences the prosecution made in the case are clearly unsound. Both podcasts are about the evidence, but they privilege different kinds of evidence.

Evidence is awkward. “Smoking guns” – pieces of evidence which uncontroversially support one and only one explanatory hypothesis – are rare. Most “smoking guns” end up being examples of evidence which at best strongly supports one hypothesis and at worst supports one hypothesis only if a certain number of assumptions are taken to be true. Many things which are called “smoking guns” aren’t; the evidence everyone says showed Richard Nixon was guilty with regards to Watergate – the missing Oval Office recordings – only look conclusive if you assume the lapse in the recording is relevant to the Watergate Affair (and not, say, a discussion about Nixon covering up the existence of a space navy).

Serial is very much a journalist’s very long form take on Adnan’s presumed innocence. Sarah Koenig ums-and-ahs over whether she thinks Adnan can really be guilty (relying heavily, I should add, on just how nice and normal he seems to her on the telephone), eventually claiming that she couldn’t have convicted him should she have been on the jury. Her reason: the State’s case against Adnan doesn’t survive scrutiny because there is no decisive which supports the claims the Prosecution made.

The argument presented by Koenig in Serial for Adnan’s likely innocence is interesting precisely because the evidence used by the Prosecution did, in fact, lead to a verdict of guilty; Koenig and her producers end up claiming that it’s not so much the evidence which decided Adnan’s guilt but, rather, the way in which it was selectively cited. Koenig and co. do not go so far as to allege misconduct from the police and the courts in this matter; it’s entirely plausible for a listener of the podcast to think “That’s just how things were done in Baltimore back then.” Which is to say that the things which allowed certain parts of the evidential record to be unquestioningly presented by the Prosecution was just a feature of the system at the time. ((Both Serial and Undisclosed emphasise that things have changed in the intervening years.))

The argument in Serial, then, is that the evidence was the evidence, but it did not support the prosecution’s take. The fact it was not challenged by the defence was a fault of the Defence. That’s a different take from that in Undisclosed. Undisclosed asserts some kind of conspiracy by the police. Or, at least, some of the hosts toy with the idea without necessarily ever stating it outright. ((I should point out that I’m only halfway through the current crop of Undisclosed episodes, so this issue of conspiracy might get addressed more fully in a later episode.))

Undisclosed takes Serial as a starting point for the analysis of the inadequacies of the prosecution of Adnan Syed, but rather than looking for the “smoking gun”, Chaudry and co. look at the inferences the police made in the case. They argue not only are these inferences wrong (such as how they rely on cellphone pings to track Adnan on the day they suspect the murder took place), but that the police knew of these issues; the investigating officers were not blithely ignorant of the inconsistencies but, rather, knowingly working around them in order to secure a conviction.

Undisclosed – if you will excuse a cliche – goes for the jugular: the police not only decided early on that Adnan was the killer, but they quite deliberately coached witnesses to ensure that he was convicted, even in the face of evidence they knew indicated he probably could not have committed the crime the way they claimed it played out. ((Not only that, but due to the success of Serial, the key witness and prosecutors have slightly changed their stories; see this interview in The Intercept))

The idea that the police secure convictions unethically is uncontroversial. ((Undisclosed spends an entire episode – almost an hour and a half – detailing previous cases of dubious and eventually overturned convictions which were investigated by the detectives who charged Adnan.)) What tends to be said these days is that it doesn’t happen as often as it did. In that respect Chaudry and co. thesis is not remarkable, especially since as lawyers they are probably much more sensitive to, and aware of, cases where the police do not play fair. However what they claim is, in the end, a conspiracy theory: the police and the prosecution knowingly kept from both the defence and the jurors evidence that would have cast doubt on Adnan’s innocence, and they have continued to maintain that the conviction is secure to this day.

Chaudry and co. come to this conclusion of conspiracy via an analysis of the way the prosecution sorted and presented the evidence. The hosts of Undisclosed are interested in how inferences were drawn from the available evidence, and how said inferences were either followed up, ignored or presented. Unlike Koenig, Chaudry and co. are willing to entertain the notion that the authorities had an agenda. ((One of the interesting aspects of Serial was Koenig’s claim that she thought it was unlikely the pursuit of Adnan as prime suspect could have been motivated by racism. Chaudry and co. seem to think it’s quite possible Adnan’s arrest and then denial of bail was – given what was said in court – very racist indeed.))

So, why is this interesting, and why is this of interest to me? Well, because evidence is something which is poorly understood by most people. People fetishise evidence, and some professionals fetishise particular kinds of evidence.

Take Serial. Koenig really wants a “smoking gun” which shows either Adnan is guilty or innocent. She does not find one, and so ends up saying that if she had been on the jury, then she could not have convicted him. That is to say she finds in favour of reasonable doubt (an understandable position), but can’t shake the idea that maybe he was guilty after all. The thing which would sway her belief – the “smoking gun” evidence – is just not available.

The Undisclosed discussion of evidence is all about poking holes in the official theory of the murder of Hae Min Lee. What the hosts are interested in is the hypotheses you can reasonably infer from other evidence, which is not just a kind of evidence, but the kind of evidence we typically rely on a day-by-day basis. For example, you think your child is eating all the biscuits, and your only evidence is that whenever you want a ginger nut there aren’t any. You know you bought some earlier, but now the kids are back from school, and there are none left. From that you infer “The kids ate the biscuits” and you charge them with this most heinous of crimes.

For the hosts of Undisclosed the issue is not that they have a smoking gun, but rather that the inferences drawn from the available evidence in no way support the idea Adnan could have committed the crime the way the State claimed he did. ((A constant issue I have with Undisclosed is how they move from “The State’s case is implausible” to the attendant claim “Adnan did not murder Hae Min Lee”. It’s not at all obvious that the details of the prosecution case being at fault means the general thesis is false (although it does show it’s hard to believe). It’s quite possible Adnan killed Hae Min Lee, the police somehow know he killed Hae Min Lee, but the actual details are so fuzzy that no clear story has emerged. But that’s by-the-by, really.)) For the people behind Undisclosed, the case falls over because the details the investigators inferred from the morass of evidence fail to survive scrutiny.

On one level this is good, because it shows up issues in the investigation, and casts doubt on the security of Adnan’s conviction. Yet it also doesn’t provide evidence for an alternative explanatory hypothesis of who committed the crime. ((Whilst the hosts of Undisclosed do think that Jay Wilds is a suspicious character, as of yet they are not claiming he was the real murderer.)) As such, the evidence which undergirds the analysis in Undisclosed can lead to a “So?” kind of response. “Sure”, people might say, “the case against Adnan looks shaky, but who else could have committed the crime?” ((I do have an issue with the strict literalism the makers of Undisclosed engage in; if someone says in their testimony “it happened a year ago”, then they take it that it pretty much happened 12 months ago. This kind of “If someone says x, then they only mean x” is a common trope in reasoning, which doesn’t really reflect the fact most of us are not all that precise when we speak. Most people gesture towards detail, as opposed to give a frank and full accounting, so the idea we should take all testimony literally does, I think, in many cases suggest radical inconsistencies where only minor details are at stake.)) That is to say, if you understand any explanation is going to rely on a certain amount of selective evidence use, and that all explanations of social phenomena (like murder) are going to have loose ends, then apparent inconsistencies can be waved away as being part of the difficulty of ever getting the full story of what really happened.

Now, this is to be expected; the hosts of Undisclosed are lawyers and all they need show is that there is reasonable doubt about the theory Adnan murdered Hae. However, an awful lot of the theory which drives their approach to instilling a feeling of reasonable doubt is about bolstering the theory the police and prosecution conspired to get a guilty verdict. Admittedly, they present a lot of evidence to support this theory, from weird plea deals with a key witness, previous cases in which the investigating officers obtained insecure convictions, the way in which evidence in favour of the defence was never given to Adnan’s legal team… It certainly looks suspicious. However, some of that suspicion comes simply from believing in the innocence of Adnan and seeking to explain away the guilty verdict.

Now, assumptions are crucial when making inferences; evidence is only evidence with respect to surrounding theories. The hosts of Undisclosed are practicing lawyers and they know how to show up the problems with rival theories. However, their strategy with dealing with the official theory is – to my mind – as frustrating as Sarah Koenig’s eventual conclusion. They present grounds for reasonable doubt, based upon good evidence of a conspiracy. Yet they downplay response to their conspiratorial claims either by simply not recognising that there could be non-conspiratorial explanations for some features of the case, or claiming such non-conspiratorial explanations are prima facie unlikely. It seems the rhetoric of defending Adnan is more important than a careful analysis.

And there’s the rub; maybe it should be. If you were really convinced that an injustice had been done, would you pepper your argument with “But, of course…” or would you do your best to persuade others of your righteousness? I wager it’s the latter, and that, just maybe, I’m judging the epistemic merits of podcasts when, really, I should be much more interested in their rhetoric.

Irvine and Mallory vs. Norgay and Hillary

[This is part of the current draft, based upon the current non-controversy about who might have made the first successful attempt at the summit of Sagarmāthā (aka. Mt. Everest), which fits in nicely, I think, with the material of my current chapter.]

George Leigh Mallory and Andrew Irvine made an attempt to reach the summit of Sagarmāthā (aka. Mt. Everest). They were last seen within several hundred metres of the summit on June the 8th, 1924 at about 1pm. Ever since, many historians and mountain-climbers have become obsessed with finding the remains of these two British mountain-climbers in the hope that amongst there personal effects will be found evidence that they successfully reached the summit before their demises.

The only fact of the matter is that Mallory and Irving were sighted at 1pm, several hundred metres from the summit. The various theories, which range from Mallory making the summit alone with Irvine’s last air-bottle to both Mallory and Irvine making the summit together, are, at best, intellectual fancies. Yet, the proponents of these theories present them as explanations for why it is that Irvine and Mallory never returned to their base camp.

The various explanations of Irvine and Mallory’s demises are, at best, Inferences to Any Old Explanation. We do not know that they reached the summit and we do not know what happened to them; there are a host of other candidate explanations for their demises, some of which are much more probable than the explanations of their demise which include a successful attempt at the summit.

The explanatory hypothesis that is used with respect to these explanations is something like the claim that Irvine and Mallory did not return to their base camp because they successfully reached the summit and then died of oxygen deprivation and exposure on the descent; another, simpler and more probable explanatory hypothesis is that they died of oxygen deprivation and exposure during their ascent. This is a much more worthwhile contender, as an explanatory hypothesis, than the more complex claim that they succeeded in their ascent and then died. Whilst the explanatory hypothesis does entail its conclusion it is not a particularly plausible explanatory hypothesis, given not only the technology of the time but also the fact that the mostly likely pathway Irvine and Mallory would have taken to the summit is now considered to be a much more dangerous traverse than the latterly discovered route subsequently taken by Norgay and Hillary; it is unlikely, given by what we now know, that Irvine and Mallory were successful in their ascent. These same considerations also make the claim that Irvine and Mallory were successful in their ascent implausible also means the explanatory hypothesis should be considered unlikely.

Now, what makes these various theories interesting is that they are often used to refute the claim that Tenzing Norgay and Edmund Hillary were the first people to reach the summit of Sagarmāthā. The candidate explanation that supports the claim that Mallory and Irvine reached the summit first is used to render the official story, that Norgay and Hillary were first, implausible, which is problematic when we consider just how problematic this particular candidate explanation is.

A Case Study in Critical Thinking: The North Head Conspiracy Theory

On Thursday I enter the wide world of corporate speaking gigs with a talk to a group of underwriters at Vero. Yay, verily, I am involved with professional development and yay, verily, I’m somewhat conflicted by the notion.I’m not a friend of Capitalism.I got the gig because one of my Continuing Education students works for Vero and thought my style would work; some challenging intellectual footwrok, a little light humour and a whole lot of love (well, no love; that would break certain ethical boundaries). I’m basing the talk on two other pieces I wrote; a critical thinking primer I gave to the librarians at the University of Auckland a few years back (when we were trying to dissuade the Library from trying to teach their own critical thinking skills programme; that’s a long story in itself) and a paper I presented at a conference a few years back, although the rewrites have almost made it into a new work.All of which is meant to explain the lack of real updates on this site; the testimony work is getting bigger and more involving in re the actual thesis and what started out as a mere paper will likely become a very important chapter in the final product. I think I may have a kind of solution to a tricky philosophical problem in re internal notions of justified belief and external notions of knowledge. A large part of my thesis will revolve around explicating the ‘Inference to Any Old Explanation’ fallacy, which is, I believe, the reason why we are so (rightfully) dismissive of claims of Conspiracy. People often make faulty inferences because they are inadequately informed or they trust unreliable sources, and testimony is a case where trusting an unreliable source can lead to having what appears to be a justified belief. The coherence of your existing beliefs affects what new beliefs you are likely to take on board and this is going to also make you more or less likely to trust particular testifiers. If you believe that the government is conspiring against you, then someone who agrees with your assessment and tells a story about how the government is conspiring is likely to be someone you are going to trust, moreso than me.

The Worse of Both Worlds

Inbetween reading academic tomes and watching ‘Doctor Who’ I do, on occasion, read spurious Conspiracy Theory literature. As of today I have finished (read that either way) with the whole ‘Bloodline of Christ’ fandango that resulted famously in ‘The Da Vinci Code’ (and should have ended more famously with acres of media coverage of the Baigent and Leigh vs. Brown case[1]).Anyway, today I finished reading Lynn Picknett and Clive Prince’s ‘The Sion Revelation.’ I met both of them in London last year at UnCon06 (although I doubt they remember me) when they gave a precis of their then just-published book. It was a good talk, focussing on the verifiable history of the Priory of Sion (the cornerstone to most of the texts on the supposedly extant bloodline of the Christian messiah) and I only didn’t buy a copy of the book because it was big and bulky and was going to take up space in a suitcase.A year later (maybe to the day) I interloaned the book (which came from Dunedin, presumably the closest source of it in a library within New Zealand). The talk Prince and Picknett made focused heavily on a peculiarly French off-shoot of Freemasonry, Synarchsim (for those of you denying the Freemason conspiracy theories[2] let it be said that whilst Freemasonry might well be benign now that doesn’t mean that a) it has always been so and b) there is also more than one kind of Freemasonry). Synarchism was the polar opposite to anarchism; the rule of the land by those destined to lead, leading those destined to be. It was an ‘everything in its place’ political philosophy that, if you accept Picknett and Prince’s thesis, is arguably one of the factors in the formation of the European Economic Community and is the real explanation of the Priory of Sion. No Templars, no Merovingians and no descent from the messiah; just Freemasons, thugs and the infiltration and subversion of secret societies.Which is all fine and good, but its just another Conspiracy Theory, isn’t it? A more plausible thesis than that of ‘The Holy Blood and the Holy Grail’ but still a Conspiracy Theory, a tentative explanation of events.These ‘more plausible’ Conspiracy Theories seem very persuasive; they, after all, up against quite wacky contenders. Admittedly, ‘The Sion Revelation’ rests upon some fairly good sources and is up front when Picknett and Prince have to make unverifiable claims, so it certainly has a degree of plausibility approaching that of an historical text but it still rests upon certain huge assumptions. It would be a mistake to assume that a ‘more plausible’ Conspiracy Theory is correct in the face of a wacky one.Yet that is a mistake people make.Which is why Conspiracy Theorists find non-Conspiracy Theorists just a little whack.–1. In case you missed it, Michael Baigent and Richard Leigh sued Dan Brown for plagiarism, arguing that he took, whole cloth, ‘The Holy Blood and the Holy Grail’ and made it into ‘The Da Vinci Code.’ Now this would have been interesting enough if they were both books intended to be fiction, but ‘The Holy Blood and the Holy Grail’ was intended to be a history book; it was meant to describe something that really happened. Just how a fiction writer can plagiarise history to write a sub-standard thriller I don’t know. Nothing about that claim makes sense. 2. Which, by and large, I do as well.      

More for my benefit than yours…

In the case of testimony, the most straightforward application of Inference to the Best Explanation would be to say that the agent infers that what the informant said is true just in case the truth of what was said is (part of) the best explanation of (among other things) the fact that the informant said it….I have so far flagged two features of Inference to the Best Explanation that make it an attractive approach to the project of providing a rule-reductive account of the acquisition of testimonial beliefs: the first is that it sanctions vertical inferences, the second that it emphasises the role of coherence considerations in inference….Nevertheless, a satisfying version of the Inference to the Best Explanation will go further, cashing out ‘best’ in terms of the symptons that guide our judgements of likelihood. Ideally, ‘best’ would be replaced by factors that have direct explanatory import, so that the account shows how we infer that the features of an explanation that would, if correct, make it the explanation that would provide the greatest understanding—the ‘loveliest’ explanation—are those that lead us to judge it also to be the explanation likeliest to be correct.Peter Lipton, ‘The Epistemology of Testimony,’ Studies in the History and Philosophy of Science, Vol. 29, No. 1, 1998