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Reference Guide on Forensic Identification Expertise--Paul C. Giannelli, Edward J. Imwinkelried, and Joseph L. Peterson
Pages 55-128

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From page 55...
... Reappraisal of Forensic Identification Expertise, 60 A. DNA Profiling and Empirical Testing, 60 B. Daubert and Empirical Testing, 62 IV. National Research Council Report on Forensic Science, 64 A. Research, 66 B. Observer Effects, 67 C. Accreditation and Certification, 68 D. Proficiency Testing, 69 E. Standard Terminology, 70 F. Laboratory Reports, 70 V. Specific Techniques, 71 A. Terminology, 71 VI.
From page 56...
... Toolmarks, 96 B. The Empirical Record, 97 C. Case Law Development, 100 IX. Bite Mark Evidence, 103 A. The Technique, 104 1.
From page 57...
... [hereinafter NRC Forensic Science Report] , available at http://www.nap.edu/catalog.
From page 58...
... For example, in its first full year of operation, the FBI laboratory processed fewer than 1000 cases.7 Several sensational cases in these formative years highlighted the value of forensic identification evidence. The Sacco and Vanzetti trial in 1921 was one of the earliest cases to rely on firearms identification evidence.8 In 1935, the extensive use of handwriting comparison testimony9 and wood evidence10 at the Lindbergh kidnapping trial raised the public consciousness of identification expertise and solidified its role in the criminal justice system.
From page 59...
... . 14.  NRC Forensic Science Report, supra note 3, at 58.
From page 60...
... ; see also NRC Forensic Science Report, supra note 3, at 40–41 (the ascendancy of DNA)
From page 61...
... . proficiency testing via blind trials."24 Commentators soon pointed out the broader implications of this development: The increased use of DNA analysis, which has undergone extensive validation, has thrown into relief the less firmly credentialed status of other forensic science identification techniques (fingerprints, fiber analysis, hair analysis, ballistics, bite marks, and tool marks)
From page 62...
... Giannelli, Wrongful Convictions and Forensic Science: The Need to Regulate Crime Labs, 86 N.C.
From page 63...
... ; Margaret A Berger, Upsetting the Balance Between Adverse Interests: The Impact of the Supreme Court's Trilogy on Expert Testimony in Toxic Tort Litigation, 64 Law & Contemp.
From page 64...
... . 48.  NRC Forensic Science Report, supra note 3.
From page 65...
... The question whether forensic evidence in a particular case is admissible under applicable law is not coterminous with the question whether there are studies confirming the scientific validity and reliability of a forensic science discipline.50 Yet, in one passage, the report remarked: "Much forensic evidence -- including, for example, bite marks and firearm and toolmark identifications -- is introduced in criminal trials without any meaningful scientific validation, determination of error rates, or reliability testing to explain the limits of the discipline."51 Moreover, the report did discuss a number of forensic techniques and, where relevant, passages from the report are cited throughout this chapter. As the NRC report explained, its primary focus is forward-looking -- to outline an "agenda for progress."52 The report's recommendations are wide-ranging, covering diverse topics such as medical examiner systems,53 interoperability of the automated fingerprint systems,54 education and training in the forensic sciences,55 codes of ethics,56 and homeland security issues.57 Some recommendations are 49.  Id.
From page 66...
... establishing and enforcing best practices for forensic science professionals and laboratories; (2) setting standards for the mandatory accreditation of crime laboratories and the mandatory certification of forensic scientists; (3)
From page 67...
... . 65.  NRC Forensic Science Report, supra note 3, at 139 n.23 & 185 n.2.
From page 68...
... . 71.  Recommendation 3; see also NRC Forensic Science Report, supra note 3, at 23 ("In short, oversight and enforcement of operating standards, certification, accreditation, and ethics are lacking in most local and state jurisdictions.")
From page 69...
... NRC Forensic Science Report, supra note 3, at 6 ("[M] ost jurisdictions do not require forensic practitioners to be certified, and most forensic science disciplines have no mandatory certification program.")
From page 70...
... . 84.  NRC Forensic Science Report, supra note 3, at 21.
From page 71...
... 89.  NRC Forensic Science Report, supra note 3, at 7.
From page 72...
... . In a case involving scientific evidence, evidentiary reliability will be based upon scientific validity."92 In forensic science, class and individual characteristics are distinguished.
From page 73...
... Jennings,101 is the first published American appellate opinion sustaining the admission of fingerprint testimony. Over the years, fingerprint analysis became the gold standard of forensic identification expertise.
From page 74...
... . 108.  NRC Forensic Science Report, supra note 3, at 139–40 & 144.
From page 75...
... . 117.  NRC Forensic Science Report, supra note 3, at 137–38.
From page 76...
... he latent print community in the United States has eschewed numerical scores and corresponding thresholds" and consequently relies "on primarily subjective criteria" in making the ultimate attribution decision.123 In making the decision, the examiner must draw on his or her personal experience to evaluate such factors as "inevitable variations" in pressure, but to date these factors have not been "characterized, quantified, or compared."124 At the conclusion of the section devoted to fingerprint analysis, the report outlined an agenda for the research it considered necessary "[t] o properly underpin the process of friction ridge identification."125 The report noted that some of these research projects have already begun.126 Fingerprint analysis raises a number of scientific issues.
From page 77...
... 135.  NRC Forensic Science Report, supra note 3, at 144. 136. Kaye, supra note 133, at 527–28.
From page 78...
... at 527. 137.  NRC Forensic Science Report, supra note 3, at 144 n.35.
From page 79...
... . 147.  NRC Forensic Science Report, supra note 3, at 139.
From page 80...
... 158.  See Bruce Budowle et al., Review of the Scientific Basis for Friction Ridge Comparisons as a Means of Identification: Committee Findings and Recommendations, 8 Forensic Sci.
From page 81...
... Cole, Comment on "Scientific Validation of Fingerprint Evidence Under Daubert," 7 Law, Probability & Risk 119 (2008) ; Jennifer Mnookin, The Validity of Latent Fingerprint Identification: Confessions of a Fingerprinting Moderate, 7 Law, Probability & Risk 127 (2008)
From page 82...
... . See NRC Forensic Science Report, supra note 3, at 43 & 105.
From page 83...
... 18 J Forensic Sci.
From page 84...
... . 181.  NRC Forensic Science Report, supra note 3, at 166.
From page 85...
... The article set out the results from each of the tests188 and then aggregated the data by computing the means for the various categories of answers: "A rather generous reading of the data would be that in 45% of the reports forensic document examiners reached the correct finding, in 36% they erred partially or completely, and in 19% they were unable to draw a conclusion."189 The above studies were conducted prior to Daubert, which was decided in 1993. After the first post-Daubert admissibility challenge to handwriting evidence 184.  NRC Forensic Science Report, supra note 3, at 164.
From page 86...
... Forensic Sci.
From page 87...
... On the other hand, the university students had a lower aggregate error rate than the professional questioned document examiners. Wolfgang Conrad, Empirische Untersuchungen uber die Urteilsgute vershiedener Gruppen von Laien und Sachvertstandigen bei der Unterscheidung authentischer und gefalschter Unterschriften [Empirical Studies Regarding the Quality of Assessments of Various Groups of Lay Persons and Experts in Differentiating Between Authentic and Forged Signatures]
From page 88...
... Peterson, The General Assumptions and Rationale of Forensic Identification, in 4 Modern Scientific Evidence: The Law and Science of Expert Testimony, supra note 104, § 29:40, at 54. 205.  Risinger et al., supra note 9.
From page 89...
... Starzecpyzel.212 In that case, the district court concluded that "forensic document examination, despite the existence of a certification program, professional journals and other trappings of science, cannot, after Daubert, be regarded as ‘scientific .
From page 90...
... 2000) (affirming the introduction of expert testimony that it was likely that the accused wrote the questioned documents)
From page 91...
... in the United States appeared in 1900.224 In the 1920s, the technique gained considerable attention because of the work of Calvin Goddard225 and played a controversial role in the Sacco and Vanzetti case during the same decade.226 Goddard also analyzed the bullet evidence in the St.Valentine's Day Massacre in 1929, in which five gangsters and two acquaintances were gunned down in Chicago.227 In 1923, the Illinois Supreme Court wrote that positive identification of a bullet was not only impossible but "preposterous."228 Seven years later, however, that court did an about-face and became one of the first courts in this country to admit firearms identification evidence.229 The technique subsequently gained widespread judicial acceptance and was not seriously challenged until recently.
From page 92...
... 3. Class characteristics Firearms identifications may be based on either bullet or cartridge case examinations.
From page 93...
... aution should be exercised in distinguishing subclass characteristics from class characteristics."239 5. Individual characteristics Bullet identification involves a comparison of the evidence bullet and a test bullet fired from the firearm.240 The two bullets are examined by means of a comparison microscope, which permits a split-screen view of the two bullets and manipulation in order to attempt to align the striations (marks)
From page 94...
... Biasotti, The Principles of Evidence Evaluation as Applied to Firearms and Tool Mark Identification, 9 J Forensic Sci.
From page 95...
... Nichols, Firearm and Toolmark Identification Criteria: A Review of the Literature, Part II, 48 J Forensic Sci.
From page 96...
... . 252.  See Jan De Kinder et al., Reference Ballistic Imaging Database Performance, 140 Forensic Sci.
From page 97...
... The committee agrees that class characteristics are helpful in narrowing the pool of tools that may have left a distinctive mark. Individual patterns from manufacture or from wear might, in some cases, be distinctive enough to suggest one particular source, but additional studies should be performed to make the process of individualization more precise and repeatable.261 The 1978 Crime Laboratory Proficiency Testing Program reported mixed results on firearms identification tests.
From page 98...
... com parisons and provided responses which agreed with the manufacturer responses 88% of the time, disagreed in only 1.4% of responses, and reported inconclusive results in 10% of cases.263 Proficiency testing on toolmark examinations has also been reported.264 For the period 1978–1999, firearms examiners performed well on their CTS proficiency tests, with only 2% to 3% of their comparisons incorrect, but with 10% to 13% of their responses inconclusive.265 The scenarios that accompanied the test materials asked examiners to compare test-fired bullets and/or cartridge cases with evidence projectiles found at a crime scene. Between 2000 and 2005, participants, again, performed very well, averaging less than 1% incorrect responses, but with inconclusive results about 10% of the time.
From page 99...
... According to one witness, in a 2005 test involving cartridge case comparisons, none of the 255 test-takers nationwide answered incorrectly. The court observed: "One could read these results to mean that the technique is foolproof, but the results might instead indicate that the test was somewhat elementary."267 In 2008, NAS published a report on computer imaging of bullets.268 Although firearms identification was not the primary focus of the investigation, a section of the report commented on this subject.269 After surveying the literature on the uniqueness, reproducibility, and permanence of individual characteristics, the committee noted that "[m]
From page 100...
... . 276.  NRC Forensic Science Report, supra note 3, at 155.
From page 101...
... 1999) (expert testimony concerning the general similarities and differences between a defendant's handwriting exemplar and a stick-up note was admissible but not the specific conclusion that the defendant was the author)
From page 102...
... Yet other courts continued to uphold admission.291 By way of example, in United States v. Williams,292 the Second Circuit upheld the admissibility of firearms identification evidence -- bullets and cartridge casings.
From page 103...
... 1996) (upholding expert testimony that three different sets of pliers recovered from the accused's house were used to cut wire and fasten a cap found in the debris from pipe bombs: "The expert's premise, that no two tools make exactly the same mark, is not challenged by any evidence in this record.
From page 104...
... One bite mark case involved dentures303 and another braces.304 A few cases have entailed bite impressions on foodstuff found at a crime scene: apple,305 piece of cheese,306 and sandwich.307 Still other cases involved dog bites.308 Bite marks occur primarily in sex-related crimes, child abuse cases, and offenses involving physical altercations, such as homicide. A survey of 101 cases reported these findings: "More than one bitemark was present in 48% of all the bite cases studied.
From page 105...
... marks can never be taken to reproduce accurately the dental features of the originator. This is due partially to the fact that bite marks generally include only a limited number of teeth.
From page 106...
... 633, 636 (1969) ; see also NRC Forensic Science Report, supra note 3, at 174 ("[B]
From page 107...
... Rawson et al., Reliability of the Scoring System of the American Board of Forensic Odontology for Human Bite Marks, 31 J Forensic Sci.
From page 108...
... . 327.  NRC Forensic Science Report, supra note 3, at 175.
From page 109...
... Additionally, there is no documented scientific data to support the hypothesis that a latent bite mark, like a latent fingerprint, is a true and accurate reflection of this uniqueness. To the contrary, what little scientific evidence that does exist clearly supports the conclusion that crime related bite marks are grossly distorted, inaccurate, and therefore unreliable as a method of identification.
From page 110...
... The defendant, however, was later exonerated through DNA testing.338 In Otero v. Warnick,339 a forensic dentist testified that the "plaintiff was the only person in the world who could have inflicted the bite marks on [the murder victim's]
From page 111...
... After Marx, bite mark evidence became widely accepted.345 By 1992, it had been introduced or noted in 193 reported cases and accepted as admissible in 35 states.346 Some courts described bite mark comparison as a "science,"347 and several cases took judicial notice of its validity.348 1. Specificity of opinion In some cases, experts testified only that a bite mark was "consistent with" the defendant's teeth.349 In other cases, they went further and opined that it is "highly probable" or "very highly probable" that the defendant made the mark.350 In still other cases, experts made positive identifications (to the exclusion of all other 344.  126 Cal.
From page 112...
... 2001) ("Both defense experts testified that these marks on the victim's body were not bite marks.")
From page 113...
... 360.  NRC Forensic Science Report, supra note 3, at 157.
From page 114...
... 363.  NRC Forensic Science Report, supra note 3, at 160.
From page 115...
... Keeping, An Attempt at Determining Probabilities in Human Scalp Hair Comparison, 19 J Forensic Sci.
From page 116...
... . 380.  NRC Forensic Science Report, supra note 3, at 159.
From page 117...
... In the 1970s the LEAA conducted its Laboratory Proficiency Testing Program.383 The crime laboratories' performance on hair analysis was the weakest. Fifty-four percent misanalyzed hair sample C and 67% submitted unacceptable responses on hair sample D.384 Followup studies between 1980 and 1991 yielded similar results.385 Summarizing the results of this series of tests, two commentators concluded: "Animal and human (body area)
From page 118...
... C Case Law Development Prior to Daubert, an overwhelming majority of courts accepted expert testimony that hair samples are microscopically indistinguishable.393 Experts often conceded that microscopic analysis did not permit a positive identification of the source.394 Nonetheless, the courts varied in how far they permitted the expert to go.
From page 119...
... Reynolds,403 a habeas case decided in 1995.There, an expert testified that, after considering approximately 25 characteristics, he concluded that the hair samples were "consistent microscopically." He then elaborated: "In other words, hairs are not an absolute identification, but they either came from this individual or there is -- could be another individual somewhere in the world that would have the same characteristics to their hair."404 The district court was "unsuccessful in its attempts to locate any indication that expert hair comparison testimony meets any of the requirements of Daubert."405 Finally, the prosecutor in closing argument declared, "There's a match."406 Even the state court had misinterpreted the evidence, writing that the "hair evidence placed [petitioner] at the decedent's apartment."407 Although the Tenth Circuit did not fault the district judge's reading of the empirical record relating to hair analysis and ultimately upheld habeas relief, that court reversed the district judge on this issue.
From page 120...
... ; see also NRC Forensic Science Report, supra note 3, at 161 n.88 (citing State v.
From page 121...
... In some, experts testified only to the limited opinion that two exhibits were "analytically indistinguishable."417 In other cases, examiners concluded that samples could have come from the same "source" or "batch."418 In still others, they stated that the samples came from the same source.419 In several cases, the experts went even further and identified a particular "box" of ammunition (usually 50 loaded cartridges, sometimes 20) as the source of the bullet recovered at the crime scene.
From page 122...
... . 429.  NRC Forensic Science Report, supra note 3, at 4.
From page 123...
... . The expert testified, based on neutron activation analysis, that two hair samples were "similar and .
From page 124...
... (reasonable scientific certainty not required where expert testifies concerning the presence of gunshot residue based on neutron activation analysis)
From page 125...
... A Pretrial Discovery Judges can monitor discovery in scientific evidence cases to ensure that disclosure is sufficiently comprehensive.451 Federal Rule 16 requires discovery of laboratory reports452 and a summary of the expert's opinion.453 The efficacy of these provisions depends on the content of the reports and the summary.The Journal of Forensic ­ Sciences, the official publication of the American Academy of Forensic Sciences, ­ published a symposium on the ethical responsibilities of forensic scientists in 1989.
From page 126...
... 457.  NRC Forensic Science Report, supra note 3, at 21.
From page 127...
... In that case, a report of a gunshot residue test based on neutron activation analysis stated the opinion that swabs "from the hands of Troedel and Hawkins contained antimony and barium in amounts typically found on the hands of a person who has discharged a firearm or has had his hands in close proximity to a discharging firearm."461 An expert testified consistently with this report at Hawkins' trial but embellished his testimony at Troedel's trial by adding the more inculpatory opinion that "Troedel had fired the murder weapon."462 In contrast, at a deposition during federal habeas proceedings, the same expert testified that "he could not, from the results of his tests, determine or say to a scientific certainty who had fired the murder weapon" and the "amount of barium and antimony on the hands of Troedel and Hawkins were basically insignificant."463 The district court found the trial testimony, "at the very least," misleading and granted relief.464 The expert claimed that the prosecutor had "pushed" him to embellish his testimony, a claim the prosecutor substantiated.465 B Defense Experts In appropriate cases, trial judges can provide the opposition with access to expert resources.
From page 128...
... In Ake v. Oklahoma,468 the Supreme Court recognized a due process right to a defense expert under certain circumstances.469 In federal trials, the Criminal Justice Act of 1964470 provides for expert assistance for indigent defendants.


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