Debunking the Scanlan Doctrine — Part 2

For some 3 decades now, attorney James P. Scanlan has flogged an elementary intuition that invariably functions to undercut efforts to highlight and remedy racial disparities in such matters as health, school discipline, voting rights and policing. In Part 1 of this post, I developed an objective exposition of this intuition that reveals its composition, its elementary nature, and its limitations. Having thus equipped a thinking person to engage critically with the Scanlan Doctrine’s content, I now aim here in Part 2 to develop a similar analytical toolkit with respect to its rhetoric. This perspective will place the Scanlan Doctrine irretrievably in the category of pseudoscience, setting the stage for a concluding Part 3—in which I will deal with a philosophical question provoked by the Scanlan Doctrine: how can an ostensibly ‘statistical’ doctrine embody ideology?


The pseudoscientific rhetorical-epistemic repertoire of the Scanlan Doctrine seems rather limited. Mr. Scanlan hardly warrants our admiration as a “sophisticated pseudo-scientist” of Freud’s stature, employing as he does only 1 of the 7 strategies of that Great Master. I refer here to #5 in Dirksen’s list: the Strategy-of-the-Proof-Given-Elsewhere. You will find this device plain enough in (e.g.) Mr. Scanlan’s response to me midway through an October ASA Connect exchange as he saw the noose tightening on his Doctrine. But really, Mr. Scanlan slathers his writings so thoroughly in this single device that (you may observe) they collapse stylistically under the weight. Nowhere in these writings do we find legerdemain to delight or entertain us. There is no daring verónica chancing others’ arguments or evidence. There is only the passage beyond an event horizon, into the infinite-regress of an imploded solipsistic singularity.

Two ‘immunizing strategies’ discussed by Boudry and Braeckman help us to understand how this ‘event horizon’ is constructed.

Changing the Rules of Play

“By undermining the standards of reasoning employed in a rational debate, one can safeguard one’s position from valid criticism.”
Boudry M, Braeckman J. Immunizing Strategies and Epistemic Defense Mechanisms. Philosophia. 2010;39(1):145-161. doi:10.1007/s11406-010-9254-9.

As part of the Scanlan Doctrine’s rhetorical toolkit, the Strategy-of-the-Proof-Given-Elsewhere serves to radically undermine the rules of rational debate. Most importantly, it converts the Doctrine into a inviolable whole, amenable neither to analysis nor criticism. Analysis, which necessarily deals in parts of things, invariably fails to cognize the coherent entirety of the Doctrine. Criticism can always be answered with a ‘suggested reading list’, and need never be met on its own terms — even on objective, graphical terms such as those developed in Part 1 of this post. (Unless I badly misread his ideological motivations, Mr. Scanlan should be horrified to learn that he is owed the grudging respect of the postmodernists, for so flagrantly playing their own game.)

This refusal to engage meaningfully with criticism has left a characteristic mark on the Scanlan Doctrine—one that led me on my earliest contact with ‘HRX’ (as I knew it then) to suspect that there was less to it than met the eye. On 10/5/2016, I offered the following criticism to Mr. Scanlan on ASA Connect:

One of the strongest signs of a sterile theory is that it cannot support technical development. I have no doubt that HRX could be formalized quite readily, and am baffled that you have not pursued this course. If you don’t do so in the next month or so, I may take up the matter myself sometime before the end of the year — either as a blog post, or something I submit to Chance or Significance. It is not inconceivable that such development will leave your HRX principle in a state that “puts it beyond use” (as they say in Northern Ireland) for the applications you seem to have been pursuing.
To be sure, I am not dismissing the argument you have been making as utterly uninteresting. I am however deeply suspicious of its failure to develop formally and evolve technically. The sheer amount of verbiage involved is astounding for so straightforward a point.
[emphasis added]

Mr. Scanlan has never engaged formally with the technical tools made available in the work of Lambert & Subramanian discussed in Part 1. Nor dare he, because to do so would compromise his Doctrine’s long-cultivated immunity from analysis and criticism. For the same reason, Mr. Scanlan will never engage meaningfully with any of the more elementary and graphically accessible objective components of my own analysis from Part 1.

Deflationary Revisions

However necessary Scanlan may have found Changing-the-Rules-of-Play in advocating his Doctrine, another immunizing strategy from the Boudry & Braeckman paper plays an even more essential—and I would argue, defining — role in guarding the Scanlan Doctrine. Boudry and Braeckman introduce the term deflationary revisions to discuss what other authors have more colorfully called “reverse switcheroos” or “Motte and Bailey Doctrines.” (I can do no better here than to refer you to the delightful discussion in §3.1.2 of the online version of their paper. What now follows assumes your familiarity with that discussion.)

As I argued in Part 1, a defining aspect of the Scanlan Doctrine is the genericity it asserts for its limit clause. Without this assertion, Mr. Scanlan would be forced each time he applies his Doctrine to provide a specific demonstration of its applicability in that case. Such engagement with particulars would prove fatal to the Doctrine and to its intended uses. Indeed, it is precisely our engagement with questions of causality that Scanlan aims to displace by means of his Doctrine. Wishing to avert any policy discussion that articulates a causal basis for the discriminatory nature of Baltimore’s policing or Texas’ voter ID law, Scanlan insists we must first get to the bottom of his Doctrine’s infinite regress. Only there, we are told, will we find the “sound footing” or “sound statistical basis” for any further discussion. In Part 3 of this post, I will demonstrate just what sort of ideological demolition Mr. Scanlan seeks to avert by this doctrinal ‘decoy’. But for present purposes, I wish simply to stress that the claimed genericity of the limit clause is mission-critical for the Doctrine.

Because deflationary revision defends so vital an organ of the Scanlan Doctrine as its genericity claim, I deem it a defining structural feature of the Doctrine. Boudry & Braeckman discuss at some length a difficult (but nevertheless fruitful) distinction between [mere] ‘immunizing strategies’ that a pseudoscience adopts from without and “full-blooded epistemic defense mechanism[s]” that originate within a pseudoscience as part of its very structure. Thus, as a part of the Scanlan Doctrine, deflationary revision seems to me most properly termed an ‘epistemic defense mechanism’.

Deflationary revision does indeed pervade the Scanlan Doctrine structurally, in a most peculiar mode of presentation Mr. Scanlan has remarkably been permitted to employ even in his peer-reviewed publications. Alongside unmistakable claims of genericity, Mr. Scanlan invariably juxtaposes data tables and other arithmetical demonstrations of a merely illustrative nature. When pressed, he retreats as follows:

We can put aside here the countless times I have explained that the patterns I describe are tendencies and discussed why there will frequently be departures from them, as well as the numerous times I have shown actual departures from them, while discussing the things one may learn from the departures.
[From a ‘Preliminary note added March 31, 2017’ on Mr. Scanlan’s ‘Scanlan Rule page’. Accessed 4/2/2017 6:30am PDT. Note incidentally how this deflationary revision is served up in conjunction with the Proof-Given-Elsewhere!]

We see here in fact the “tandem maneuvers” described by André Kukla (again, I refer you to §3.1.2 of Boudry & Braeckman, as they quote at length from Kukla):

  • Switcheroo: “starting with a hypothesis that’s amenable to a range of interpretations, giving arguments that support a weak version, and thenceforth pretending that one of the stronger versions has been established.”
  • Reverse switcheroo: “you put forth a strong version of the hypothesis, and when it gets into trouble, you retreat to a weaker version, pretending that it was the weaker thesis that you had in mind all along.”

Thus, Scanlan pairs the switcheroo that is his standard account of the Scanlan Rule with the reverse switcheroo (aka, deflationary revision) as seen above in his ‘Preliminary note’. As Kukla goes on to point out in Boudry and Braeckman’s extended quotation,

“Switcheroos and reverse switcheroos can be performed in tandem, and the cycle can be repeated ad infinitum. A judicious application of this strategy enables one to maintain an indefensible position forever.” — André Kukla

Not quite forever, one may hope! By exposing the pseudoscientific character of the Scanlan Doctrine, I hope to enable self-respecting statisticians and social scientists to turn their attention to the substantive matters we ought to argue over. The concluding Part 3 of this post will contain some indications as to the character of the arguments I think worthy of us.

I welcome your comments below.