Forensic Anthropology

Anthropological facial 'reconstruction' - recognizing the fallacies, 'unembracing' the errors, and realizing method limits

CN Stephan Department of Anatomical Sciences, Bioanthropology and Comparative Anatomy Research Unit, The University of Adelaide, Adelaide, 5005, Australia

Introduction Although it has been said that "Everyone dislikes a sudden loud noise, but worse still if you are half-asleep at the time" [I] p.123, it has also been said that "a none too-gentle shaking does us good" (D. Lewis, cited in [2] p. 18). Like it or not, the noise and the shaking have been taking place for decades in the world of facial "reconstruction" with a consistent influx of critical papers into the published literature. Most notable are those by Suk [3] and Montagu [4], respectively entitled "Fallacies of anthropological identifications" and "A study of man embracing error", but for other examples see [3-101. However, these critical papers seem not to have much impact, at least generally. Although there appear to be a significant number of bioanthropologists who approach the method of facial approximation with caution and scepticism, many other people appear to readily embrace the method as presented by practitioners without any rigorous empirical justification. If you need to be convinced of this ask around the bioanthropologists at the next national forensic meeting you attend and contrast the reservations they hold to those of lay individuals after a broadcast of a television programme illustrating the method or opinions held by practitioners at an "inhouse" facial approximation conference.

Given the lucid nature of the flaws in traditionallcurrent facial "reconstruction" methods (see below) it seems surprising the method has not been regarded with more scepticism by most individuals. This is even more perplexing given all the noise and the shaking of the past (which at times has been rather strong, see e.g., [3, 4, 111). Perhaps this suggests that the noise and shaking has not been clear or intense enough; has been ignored by most; or has simply not reached the lay individual. Whatever the case, caution towards the ambitious claims of the facial approximation process appears to have been largely disregarded by some. This paper once again draws caution to the claim that faces closely representing target individuals can be built from skulls in a recognizable fashion and re-emphasizes some of the main fallacies that have been widely established. The paper also presents new evidence for other specific soft tissue prediction fallacies, discusses some of the sources of the fallacies in general (e.g., disciplinary politics) and proposes a possible way through the "mess". Once pointed out, the misleading notions of the traditional and current facial approximation processes may seem obvious to many. This illustrates the effectiveness of the ploys employed to maintain these notions, even if done unintentionally

by some. Even so, I make no apologies here for directly addressing some of these perhaps sensitive issues. Not to do so would jeopardize reason and would be a surrendering to political agendas and ploys counter to scientific endeavours.

Four primary fallacies of facial "reconstruction" Fallacy 1: We can predict facial soft tissues from the skull, creating faces that are correctly recognizable Everyone agrees that to be able to build a face from a person's skull that is representative of and recognizable as the target is an awe inspiring feat - if it can be done. The intricacy and complexity of the soft tissues overlying the skull is significant and to be able to predict them accurately and precisely from the skull alone would definitely be something special. Both of these aspects are precisely what facial approximation practitioners claim the method achieves [12-141. However, there are several major limitations that render traditional/current facial approximation methods unlikely to generate accurate face anatomies and hence visages that can be purposefully and correctly recognized.

Firstly much of the soft tissue of the face is not directly associated with the skull making its prediction troublesome, perhaps even impossible [3,4]. Facial approximation practitioners (e.g., [12-14]), quite rightly, recognize that the muscles of the face appear to be a significant feature to predict because they make up a relatively large portion of the facial soft tissue bulk and probably have one of the strongest associations with the skull. However, the prediction of these muscles is troublesome. Some craniofacial muscles have no attachment to the skull but rather originate and insert into the soft tissue alone (e.g., risorious, and orbicularis oris). To say that this makes their accurate prediction difficult is likely to be an understatement, for the errors in predicting soft tissue features that have little or no association with the skull are probably large. Furthermore, muscle determination in these cases will be purely subjective and empirically unjustifiable. Many other craniofacial muscles also only have one attachment to the bone, the other being into the soft tissues (e.g., zygomaticus major and minor, levator labii

O The Forensic Science Society 2003 Key words Forensic science, facial reproduction, facial approximation, soft tissue prediction, art, exocanthion, lateral canthal tendon.

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superiors, mentalis, depressor anguli oris etc.), again making accurate prediction unlikely. The structure and even presence of some of these muscles is highly variable [15, 161 and often delicate, again making prediction difficult at the level of the individual. Out of roughly 30 individual muscles contributing to the surface anatomy of the face only two pairs, temporalis and masseter, have "well demarcated" origins and insertions on the skull that appear to lend themselves to prediction. While the general attachment site locations for all the facial muscles are known, no studies appear to have systematically assessed the specific attachment boundaries of the facial muscles with respect to muscle prediction. Certainly any such studies have not been cited in the facial approximation literature, suggesting that if any do exist the information they provide is not being used in facial approximation. The fact is that at present we do not know what anatomical features precisely indicate muscle attachment boundaries, if any such features are consistent across all muscles of the face, and if these features can be determined macroscopically. Nor are we aware of any precise correlations of these attachment sites with specific muscle body shapes or bulks. Of course general correlations are known to exist like if the attachment site is "robust" the muscle is likely to be "powerful" and hence "large", but this is insufficient for precisely determining the demarcations of insertionlorigin and the bulk and shape of the muscle. For example, how robust does an attachment site have to be to indicate a large muscle? How large is a "large" muscle meant to be? Where on, or around, a muscle insertion tubercle does the muscle actually insert? What bony surface features can be used to precisely determine the muscle attachment boundaries for delicate muscles of the face? Can they been seen with the naked eye? What is the error involved? Certainly the subjectivity currently required for predicting perhaps the bulkiest structures intimately associated with the skull (the facial muscles) does not augur well for other soft tissue prediction, like subcutaneous fat, that have weaker associations with the bone.

Secondly, the soft tissue prediction guidelines facial approximation practitioners use are relatively few, particularly those that have been tested, as any review of the scientific literature will demonstrate [ l l , 171. Almost all soft tissue prediction guidelines that have been employed are published without any formal empirical evidence for the anatomical relationships claimed. Since large assumptions are made when using these subjective guidelines, accurate building of face features seems unlikely. Even when subjective guidelines are used for feature prediction there is much trait anatomy unaccounted for and which is left up to the intuition of the practitioner. For example, in building the lips there now exist tested guidelines for mouth width [ l l , 181, various guidelines for determining stomion height [19,20], and untested guidelines for determining lip height [14, 21, 221. However, the actual shape and fullness of the lips can only be intuitively derived. While a general indication may be gleaned from the occlusal pattern of the teeth, this does not help greatly since individuals with similar occlusions do not all have exactly the same shaped lips.

Even books totally devoted to the topic of facial approximation

appear to cite disproportionately few guidelines for the job at hand. For example, Gerasimov in "The Face Finder" (1971) describes the facial "reconstruction" technique in 10 pages (5%) of a 199 page book dedicated to the topic. Prag and Neave [12] also appear to gloss over the techniques of facial "reconstruction" in "Making Faces", dedicating less than 10 pages (4%) of the 256 page book to specific methods. The dedication of such small segments of writing (-10 pages) to techniques that take on such a huge task definitely seems less than sufficient. One certainly has to wonder if the guidelines cited in these books are the only ones used. Taylor and Gatliff [14, 211 provide a somewhat more comprehensive review of facial approximation methods over several chapters, however, here again the guidelines presented are mostly those relatively few reported in the general literature. How can facial approximation practitioners realistically expect that a face, built from the skull using so few guidelines, can be specifically and purposefully recognized? The fact that so relatively few guidelines are "recycled" throughout the literature by many authors suggests that facial approximation practitioners are not keeping a horde of guidelines to themselves but rather these are the only ones that are used.

Thirdly, many of the guidelines used in the facial "reconstruction" process appear to have been based on informal observations and many have not been subjected to any empirical tests that have been published, so their accuracy is unknown. Due to time restraints, individuals cannot test all methods before undertaking a facial approximation so they must rely on advice of others for at least some soft tissue prediction guidelines. Consequently, many of these subjective methods have been blindly followed for years, and it seems likely that at least some have consequently become regarded as established methods even though they have never been empirically demonstrated or justified. While unavoidable in many instances (not every practitioner can test every method), this is not favourable since many of the methods being used may be inaccurate [6]. Indeed, recent tests of some of these methods have shown many guidelines to display large errors, like some of those for determining mouth width [ l l ] , eyeball projection [6, 231, ear height [24], nose projection and pronasale position [I71 and superciliare position [25]. The next two paragraphs illustrate the significance of this point by examining another face trait, lateral canthus position, for which traditional facial "reconstruction" guidelines are shown to be inaccurate by evidence already existing in the published literature.

The lateral canthus (outer corner of the eye slit otherwise known as the ecto- or exo-canthion) has been estimated according to three methods: ( I ) that it falls 5 mm medial to the lateral orbital wall (Krogman cited in [26]); (2) that it falls 3 to 4 mm medial to the lateral orbital wall [27]; and (3) that the exocanthion falls on or just medial to the lateral orbital wall [28]. A variation of method 3 is that the exocanthion falls 1 mm medial to the outer orbital wall [29]. The existence of multiple guidelines for predicting the same trait, which is the case not just for the lateral canthus but also many other traits (e.g. mouth width [ l l ] , and nose projection [17] etc.), explicitly and undisputedly indicates a

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lack of soft to hard tissue relationship knowledge, for it is logically and practically impossible for all of these guidelines to be (on average) correct. As indicated by Stephan and Henneberg [lo], the fact that many differing guidelines exist for determining the same trait suggests that the accuracies of these guidelines are unknown, as otherwise would not the most accurate be disproportionately cited and the others abandoned? Although it is impossible for two or more soft tissue prediction guidelines to be correct if they give different results, it is logically possible that at least some, or possibly all of the guidelines are incorrect. Certainly the direct relationship of guideline three above seems questionable with respect to the typical anatomy of individuals, since visual inspection and palpation easily indicate that in most individuals the lateral orbital wall falls lateral to the exocanthion.

Although not used by facial approximation practitioners up until this point, there is published empirical evidence describing lateral canthus position in cadaveric material. This research so far suggests that all three of the above guidelines are incorrect. A study by Rosenstein and colleagues [30] determined the distance the lateral canthus falls away from the lateral orbital wall, relative to the coronal plane (Rosenstein, 2003, personal communication) in 21 cadavers. They found the average distance between the lateral canthus and the lateral orbital wall to be 7.5 mm (SD = 2.8 mm, range: 2-12 mm), a value between two- and seven-times greater than that indicated by traditional facial approximation guidelines. Furthermore a study by Gioia and colleagues [3 11 in 1987 reported bilateral dissections of eight human cadavers where they were able to measure the long axis of the lateral canthal tendon and calculate its average length (n=16). The value they found was 10.6 mm, with a standard deviation of 0.9 mm. Since the lateral canthal ligament attaches on average 1.5 mm behind the orbital margin [3 11, the length of the lateral canthal tendon reported by Gioia and colleagues [3 1 ] appears to corroborate findings by Rosenstein and colleagues [30], as together they indicate that the lateral canthus falls about 6 mm anterior to the lateral orbital margin. This is a value that seems reasonable given that the cornea is reported to project about 16 mm anterior to the lateral orbital rim; see for review [6]. Therefore, while the results of Rosenstein and colleagues' study [30] suggest that Krogman's (cited in [26]), Angel's [27], Sills' [29], and even Yoshino and Seta's [28] reports are possible in some instances, on average they will tend to grossly under predict the distance the lateral canthus falls away from the lateral orbit in the majority of individuals.

Fourthly, although general trends (e.g., central tendencies, correlations, regressions etc.) may be one of the better ways of approximating values for many individuals (as done above), they are extremely limited when predicting individual values since errors may be considerable [5]. Hence, inaccuracy in soft tissue prediction is inevitable even if the soft tissue guidelines have been empirically justified and is probably rather large due to error accumulation when several individual soft tissue guidelines are sequentially employed. A better approach to building faces than using central tendencies would be to use soft tissue prediction guidelines that are individually "tailored" to each

skull, by being based on specific anatomical morphologies. This is theoretically possible using the Russian method of facial "reconstruction" (see [12, 13]), however it is practically impossible at present given current anatomical knowledge. In comparison to straight averages, regression equations are advantaged for they take into account other relationships, but even regression equations are not optimal since they are also based on general trends and hence may have considerable prediction errors.

Additionally, since there are relatively few tested soft to hard tissue relationships currently known for modern humans, it is clear that the use of facial approximation techniques on ancestral skulls of modern Homo are fundamentally flawed, as previously reported by Montagu [4]. The decomposition of the soft tissue parts of paleoanthropological beings makes it impossible for the detail of their actual soft tissue face morphology and variability to be known, as well as the variability of the relationship between the hard and the soft tissue. As a result, the faces of earlier human ancestors cannot be objectively constructed or tested. Attempts based on modem ape morphologies (and variabilities) are likely to be heavily biased, grossly inaccurate, and invalid because the hard to soft tissue relationships of modem apes are unlikely to be the same as hominid ancestors due to changes arising from secular trends and evolutionary forces [4]. Hence any facial "reconstructions" of earlier hominids are likely to be misleading [4].

Fallacy 2: Faces are reconstructed from skulls The fallacy that practitioners can predict accurately the soft tissues of the face has wide ramifications since it generates other fallacies that act to reinforce this initial fallacy. An example is the most common name given to the method of building a face from a skull - "facial reconstruction". Apart from the disadvantage that this name is already used to describe other procedures, like the process of reassembling skull fragments [32] and methods of medical facial surgery [33], "reconstmction" implies exactness [20], something that current methods of building faces from skulls cannot claim (even if the whole process was empirically tested and justified). The use of such a name, also automatically distils in individuals from the outset a sense that the method is highly credible for its name sounds technical and scientific. Other synonyms, like "facial reproduction" [20], do likewise. Many agree that "facial approximation" is the most appropriate term, for it indicates inaccuracy [lo, 14,201; but why then has it not been commonly used? It seems "facial reconstruction" is likely to generate more interest and be more influential (compare the difference in aura surrounding "facial reconstruction" as opposed to "facial approximation"). Some indicate that they do not use "facial approximation" because it is not in general circulation [14, 341. This, however, is a poor excuse given the hugely misleading nature of the term, which is of course its main advantage and one that benefits any authors using it. Furthermore, as anyone involved in facial approximation has experienced, the beliefs of lay individuals that facial "reconstruction" actually works goes hand-in-hand with awe. Remarks like "wow, you have to be pretty smart/knowledgeable to be able to do such a complex

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task" are not uncommon. Of course, if the term "facial approximation" was used instead of "facial reconstruction" less awe would be generated, and practitioners might receive less fame and attention.

Fallacy 3: Facial approximation is creditable because it is partly science Not only is it often implied that facial approximation is an accurate technique but also it is often associated with science, either being described as a blend of science and art [14, 35-40], or as pure science, e.g., Wilkinson, Neave and Smith [41] p.111 state that "Facial reconstruction is the scientific interpretation of the skull". There is little doubt that associating a method with science increases its credibility, self-worth and acceptability with lay individuals, but it also overemphasizes the rigour of the method [6, 71, and is hence misleading.

Suggesting that facial approximation is partly a scientific method is not wrong since there are a few components that are scientifically derived like various average soft tissue depth data. However, the methods based on these scientifically derived data form only a small part of the overall facial approximation process, which overwhelmingly relies on untested and subjective soft tissue prediction guidelines. See for examples the guidelines presented in the books mentioned above. Consequently, it is unjustifiable and misleading to refer to the entirety of the facial approximation method as a blend of science and art, or as a science in itself, since it includes much, much, (much) more "art" than systematically tested methods [6]. The fact that several of the commonly used subjective guidelines when scientifically evaluated have been found to be inaccurate, see e.g., [6, 11, 17, 23-25], strongly emphasizes the point that traditional facial approximation methods are not scientific, for if they were scientific and their error known previously surely these methods would have been abandoned or improved upon.

Fallacy 4: We know facial "reconstruction" works (i .e. , generates recognitions from the constructed faces) because it has been successful in forensic cases This is a common defence to criticism of the method of facial approximation, however it is a weak one. Certainly facial approximation has been successful in generating leadsltentative identifications in at least some forensic cases involving unidentified human remains [12, 42491. Reported practitioner success rates are also high: Gerasimov [13] claims 100% success; Bender [50] 85%; Wilkinson [40] 75%; Gatliff [46] 70%; and others claim more conservative but still high rates, for example Neave [12] 50-60%. This evidence indicates that facial approximations are identified at least occasionally, but this does not mean that the faces are being recognized purposefully, which is the intended goal of facial approximation [12, 141. Facial approximation success may be due to factors independent of the facial approximation, for example, contextual information [7] or chance [lo] and may also be influenced by other factors, like broadness of media coverage [8]. Additionally, there seem to be many cases where facial approximation was not successful, e.g., [7, 9, 101, indicating that there are certainly instances where facial approximation does not work. Furthermore, it also seems likely that many unsuccessful cases go unreported andlor

unpublished, resulting in a biased account of facial approximation success when examining published literature [lo]. Hence, forensic case success does not conclusively or convincingly indicate that facial approximation methods achieve their aim: purposeful true positive recognitions of target individuals.

Reported practitioner success may also be unreliable since the reporters (facial approximation practitioners) are usually very enthusiastic about their work. Some have indicated that recognition rates have appeared to increase from around 30% in the late 1980s as competition between practitioners increased and peers started quoting their own (often higher) success rates (Taylor R, 2001 personal communication). Such trends are even evident within the last few years. For example, reported success of R. Neave's method which is often described as either the "British" or "Manchester" method has increased from -55% [12] to 75% [40] over a five year period, without published method changes. Furthermore, it seems that in some instances success rates may be biased depending on who is quoting them. For example, although Gatliff has claimed a 70% recognition rate [46], Wilkinson, who uses the Neave, method indicates that the American method as practiced by Gatliff only achieves a 65% success rate, while the British method as used by Neave is 75% successful [40], even though Neave himself reports that Gatliff has 72% success 1121 p.18 and that the success rate of the "British" (or "Manchester") method is between 50 and 60% [12] p. 33. The inconsistency in reports combined with confounding factors influencing casework success suggest that much caution should be employed when gauging facial approximation success based on reported practitioner success and the success of individual forensic cases.

'Unernbracing' the errors Many of the fallacies presented above act to increase method credibility by stretching, manipulating or even disregarding reason largely as a result of disciplinary politics. The ability of facial approximation to hide behind this screen of artificial validity has effectively seen the methods "sail on" over the last 200 years with few changes despite the computerization of some methods. Four primary examples illustrate this claim: (1) subjective, empirically untested, soft tissue prediction guidelines still form the fundamental basis of the facial "reconstruction" process as they did in the past; (2) average soft tissue depths as developed in the late 1800s have essentially been used unchanged up until this point of time (although data collection methods have been refined). Recent developments by Simpson and Henneberg [51] linking soft tissue depths with face size certainly seem to be a promising future exception here but since they have not been reported to be employed in the facial approximation process they remain irrelevant to this discussion at this time; (3) facial "reconstruction" is still being used in paleoanthropology despite elemental flaws in this application; and (4) most lay individuals still appear to be of the misleading opinion that facial "reconstruction" does actually result in visages that are recognizable as the person to whom the skull belonged, even though little if any evidence exists for this relationship; see for example [9, 10, 52-54].

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If any improvements in the method are to be made the weaknesses of current methods must first be established and recognized, so direction for improvement can be determined. This must be done using scientific tests for these seem to be the best practical ways to currently gauge the "truth" of any claim (whether derived by deduction, induction, intuition, magic, etc.) within the current constructs of Western society [55-571. Why then has this not been done previously? Perhaps those who have been working in the field for some time could give the best answer. Since this is not possible here, I shall opt for a brief analysis of the history of facial approximation that should give a fairly good impression of what was happening.

One of the most significant advances in facial approximation was in the late 1800s when facial approximation became based on average soft tissue depths [58-601. This was a first step towards using quantitative methods in the facial approximation process and set the scene for the use of science (testing the "falsifiability" of hypotheses) in the discipline. Scientific testing and "progress" would therefore seem certain to follow from this point onwards but this has not happened. Two factors seem likely to have offset this process.

Firstly, practitioners appear to have gotten ahead of themselves (as anyone creating facial approximations today is still doing) by "jumping in" and building a whole head before they have enough tested and reliable methods to do it properly. For example, while tested average soft tissue depths are a large advantage for building faces from skulls they are utterly insufficient without other tested guidelines, yet despite this faces were still being constructed and limitations were rarely recognized; exceptions are [3, 4, 9, 101. Some would argue that "straight" average soft tissue depth data, derived for estimating soft tissue facial bulk, are insufficient to achieve their aim [5 11 (see explanations above). A statement with which others [5] and I would also agree.

In forensics the premature employment of methods may be justifiable since any identification attempt that may generate the identification of a victim is well worth trying, even if it happens to work by chance - but as illustrated above any success of the method here cannot verify its ability to generate purposeful recognitions since there are too many confounding variables. Even if untested guidelines are used and happen to "work" they should not necessarily be used again on the basis that they "worked" previously, rather they need to be specifically tested. This testing has not happened in the past, rather facial "reconstructions" have been constructed for years using untested methods with so called "practitioner success rates" being used for method justification.

Secondly, artists became involved in the facial approximation method because some scientists appeared not to possess the dexterity required to build a realistic face. This led to artists constructing the faces with scientists supposedly looking over their shoulder to ensure the methods were being rigorously applied; see for example [9, 14, 52, 60, 611. Inevitably, other "artistic rules of thumb", artistic canons, and subjective

guidelines that artists use became included in the method, as for example that the height of the ear equals the height of the nose [22]. Since artists were the ones constructing the faces they become renowned for much of the facial approximation process and also became largely responsible for much of the field since they were the ones primarily working at the "forefront" of the discipline. Hence, scientific testing developed little. Attempts by some to revive scientific testing of the method in the 1980s were met with resistance and consequently some of these scientists ceased pursuing "serious" facial approximation research in an attempt to avoid conflict with others in the profession. Facial approximation, therefore, became largely isolated from any active scientific research, yet it continued to be readily associated with science, seemingly in an attempt to maintain the credibility of the method.

Given that some have established careers on facial approximation and received fame for it, it is perhaps not unexpected that there seems to be resistance to putting traditional methods to the test now. On several occasions it has been reiterated that any scientific research should be presented in a "positive manner" [62] p.469. It has also been suggested that improvements to the technique should be emphasized rather than highlighting what does not work. For example, an artist wrote to me in 2001 stating: "I truly hope that future efforts will emphasize ways to improve rather than tear down the process". Both these statements show a misunderstanding of how science works. Scientific conclusions are always "positive" - they can never be "negative". Science depends on testing hypotheses (possible outcomes of a difference, the confidence of which is represented by a "p" value indicating the possibility of a type 1 error) or null-hypotheses (possible outcomes of no difference, the confidence of which is represented by the "power", or I-b, indicating the possibility of a type I1 error). A hypothesis or a null-hypothesis must be falsifiable for it to be testable and hence scientific, for we cannot tell if a proposition is true, but only if it appears to be false [55,56]. Therefore whether a difference or no difference is found, the results of a study always add to knowledge and are hence helpful or "positive". Since scientific knowledge is "refined through falsification, those findings that show previous notions to be incorrect are perhaps the most valuable since they can bring even closer approximations of the truth than before [55,56]. Hence, findings some people interpret as being "negative" are actually the most "positive" type of scientific conclusions possible. For if research findings only reiterated existing knowledge few new findings would emerge or improvements be made.

Scientific findings that show particular parts of the facial approximation method do not work well do not "tear the method down", rather they allow us to determine at what stage the method is at, setting a basis from which the method can be further built and improved. Without knowing what needs to be improved in the method, i.e., its weaknesses, efficient progress cannot be made. If no weaknesses were known to exist there would certainly be little reason for making any improvements. Indeed recent tests finding inaccuracies in the method have led to attempts to improve methods (see e.g., [6, 11, 17, 18, 251).

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Few methods can be expected to be without flaws and in this respect facial approximation is no different. However, the problem in facial approximation is that major method weaknesses have not been recognized in the past and many individuals have consequently been misled. In facial "reconstruction" the flaws may be so large and numerous as to prevent the method from even coming close to achieving its aim. The only "tearing down" any scientific results have the potential to do to the facial "reconstruction" process is the tearing down of misleading notions that faces created from skulls using traditional methods result in purposeful and specific true positive recognitions, if in fact these notions are misleading. It seems worth noting here the perhaps worrisome situation that untested soft tissue prediction guidelines, some of which are used in the facial approximation process, are also being used for skull-face superimposition techniques.

The only way forward is for the facial approximation method to become empirically tested and verified which means the method must become scientific. This is a significant advantage if the method is to be used in forensics, for scientific methods must be repeatable. Despite such advantages of science, some have rejected results that do not sit comfortably with traditional claims. For example, after the publication of a paper [6] that showed that the guideline for predicting globe projection as commonly cited over the past 40 years in the literature was inaccurate, a well known facial approximation artist wrote to the author stating "In my opinion, you are not qualified to evaluate or research the fine points [of facial "reconstruction"] and tell me what I should or should not use". Certainly, subjective evaluations of the qualifications of investigators should not form the basis for assessing scientific studies but rather the substance of the scientific studies themselves. Everyone is entitled to use whatever methods they wish and hold their own opinions, but if facial 'reconstruction' is to be publicized in association with science, as artists clearly commonly do (e.g., [14, 21, 35401) then they must also recognize the scientific findings reported in research studies. Only after a logical review of the actual research can the reported results be judged. It is worth noting here that the inaccuracy in globe projection according to the guideline in question (see [6]) has been replicated by independent investigators using different methods, see [23].

Despite the controversy of the facial approximation method and associated fallacies that have been promoted over its lifetime, the facial approximation technique is useful to forensic science. Even if facial approximation does not reliably generate specific and purposeful recognitions it draws public attention which increases case profile and the likelihood of victim identification via other means [7, 8, 10, 111. The finding that facial approximation infrequently results in specific and purposeful facial recognition [lo] does not mean, as has been repeatedly indicated in the literature recently, that "facial approximation would be detrimental to any forensic identification case", see [23] p. 12, [41] p. 112. If the method results in an identification, despite being unreliable or working by chance, then it is helpful (as even the original article [lo] cited by Wilkinson and colleagues indicates). Even if the method is unreliable, it should

be employed at the appropriate time in an attempt to identify the skeletal remains, for the task of identification is important for easing family concern and grieving, and for assisting in the apprehension of the offenderls [63]. Since a significant advantage of the facial approximation method lies in its ability to generate much public interest, it is important that attempts are made to maintain the bewilderment factor of the method and the interest of the public. A way to do this without misleading individuals, is to "simply" increase the accuracy and reliability of the method by scientific testing [ l I].

Summary Despite being practised for over the last 200 years, facial approximation methods remain in their infancy as the soft tissue prediction methods employed have not been tested and justified. Scientific testing is the only way forward and much of it is needed. The lack of systematic scientific tests in the past has enabled many misleading notions to become established. Many of these notions appear to have arisen and been sustained as a result of practitioner biases - this is clearly evident even in the name commonly used to describe the method of building faces from skulls, for "facial reconstruction" implies everything the method is not, e.g., technical/scientific, exact, and credible. Although facial approximation methods are useful for forensic investigation (even if they do not generate identifications through true positive recognitions of the faces), the public should beware of the marketing and political ploys employed within the profession. These ploys give rise to some impressive, but unjustifiable claims - but do not just take my word for it; evaluate the evidence for yourself with disregard to the indoctrination waged by the facial "reconstruction" field in general, including that promoted by what I have had to say here. Use your own reason and intellect and see which conclusions you reach.

Acknowledgements I am grateful to Prof. Maciej Henneberg for providing comments on an earlier draft of this paper. I also acknowledge titles of papers by MFA. Montagu [3, 41 and V. Suk [3, 41, which were adapted here to help provide a "reoccurring" theme for this paper.

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