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(e) a person accused or convicted of a criminal offence should have adequate access to relevant DNA evidence and, where tested, to test results and interpretation; Cecil and Willging (1994, p. 542). In some cases, defendants visited court-appointed experts to review the work of state experts. For example, Taylor v Commonwealth, 1995 WL 808189 (Va. Ct. App. 1995) (an unpublished statement refers to confirmation “by an independent DNA expert appointed by the trial court at the request of the accused”). Other opinions refer to independent experts, without specifying the method of their appointment. For example, Williams v State, 265 Ga. 351, 455 p.E.

2d 836 (1995) (stating that “an independent geneticist agreed with the DNA results”). Probability ratios were used in State v Klindt, 389 N.W.2d 670 (Iowa 1986) (discussed below) and are commonly accepted in ancestry disputes, where they are known as the “paternity index” (see Chapter 5). For example, Kaye, 1989; Aickin and Kaye, 1983; McCormick 1992, § 212. Some state laws use them to create a presumption of paternity (Kaye, 1990a, b, c). The practice of providing an index of paternity has been applied to criminal cases where genetic ancestry is used to indicate the identity of the perpetrator. For example, State v Skipper, 228 Conn. 610, 637 A.2d 1101 (1994); Davis v State, 476 N.E.2d 127 (Ind. Ct. App. 1985); State v Weeks, 891 p.2d 477 (Mont. 1995); State v Spann, 130 N.J.

484, 617 A.2d 247 (1993): State v Jackson, 320 N.C. 452, 358 N.E.2d 679 (1987). In some of these cases, some appellate courts disapproved of biostatistical representations, but none explicitly condemned the use of the probability ratio. What does this mean for the accused? Let`s look at the pros and cons of DNA evidence in court and how it benefits or works against the accused. State v. Streich, 658 A.2d 38 (Vt. 1995) (“We note that courts that refuse to accept statistics based on the unchanged product method continue to rely on the narrower Frye standard,” but the court reached the same conclusion under the Daubert standard). (iii) indication of the protocol used for the audit and deviations from the protocol; (c) Valid statistical estimates of population frequency should be allowed. Since DNA testing became widespread, the sentences of more than 375 convicted persons have been quashed on the basis of DNA evidence. In the decades leading up to DNA testing, lawyers and jurors had to rely on eyewitness accounts, fingerprints and other circumstantial evidence to decide guilt or innocence. (g) databases should be extended to other categories of persons as resources become available, data protection concerns are addressed and information security is ensured. (c) If consent is obtained in accordance with paragraph (b) of this standard, each person should be informed of the reason for the request and the right to refuse it, and consent should be obtained in writing.

Prior to Daubert, many state and federal courts had interpreted their rules of evidence so as not to contain a rigid requirement of general acceptance. NRC 1992 Report (p. 192). 137) described the “auxiliary standard” used in these countries as the following factors: “general acceptance of scientific principles”, “qualifications of experts who testify to the new scientific principle, application in which the new technique was applied, possibility of error of the technique, existence of specialized literature dealing with the technique and its novelty”. Since Daubert, many state courts have suggested that their “ancillary standard” is essentially identical to the approach set out in Daubert; a few described their rules as more permissive.16 With respect to the latter issue – the ability to distinguish sources – courts have required more convincing evidence of the exact degree of individualization achieved by DNA testing than by any other commonly used forensic technique. Some courts have found it necessary for experts to prove not only that DNA profiles usually vary from person to person, but also to provide undisputed quantitative estimates of the rarity of identifying characteristics within certain groups and subgroups. It is doubtful that many other forms of identifying evidence can withstand comparable requirements.2 Lawyers and jurists have debated whether DNA evidence warrants this special treatment.3 We do not take sides in such legal debates, but we emphasize that both issues – the scientific acceptance of the laboratory method for comparing samples and the idea that the characteristics studied in the laboratory are proof of identity – are different. Therefore, this chapter describes the implications of our findings on the state of scientific knowledge for both statements on the extent to which DNA samples match and for statements on the likelihood of such matches. (x) a list of collected items that have reason to believe that they contain DNA evidence, but that have been destroyed or lost or are no longer otherwise available; When solid containers are used, sometimes a dispute arises about the frequency of a fragment close to the limit of two containers.

In Chapter 5, we found that the sum of the frequencies of the two cells, as recommended in the 1992 NRC report, always provided an upper limit for allele frequency. At least one court has found that, under the established approach, this summary is “the only method that can be described as generally accepted” (United States v. Porter, 1994 WL 742297 [DC Super. Ct. 17 Nov. 1994]). However, as we noted, using the allele frequency of the larger tray provides a better approximation of the more accurate number obtained from floating bins. It is important to understand that DNA is a widely used form of evidence in criminal cases and, if used correctly, can change an accused`s life for the better, but also for the worse. Strengths, Limitations and Controversies of DNA Evidence by Naseam Rachel Behrouzfard examines the pros and cons of DNA evidence in criminal cases: State v Bogan, 183 Ariz. 506, 905 P.2d 515 (Ct. App. 1995), rev.

granted; State v. Hummert, No. CR 90-05559 (Super. Ct. Maricopa Co. Apr. 16, 1991), rev `d for the non-exclusion of testimony asserting that the agreement was unique, 183 Ariz. 493, 905 P.2d 493 (Ct. App. 1994), rev.; State v.

DeSpain, No. 15589 (Supreme Court of Yuma Co., 12 February 1991); State v. Pennell, 584 A.2d 513 (Del. 1989); State v Schwartz, 447 N.W.2d 422, 428 (Minn. 1989); State V Alt, 504 N.W.2d 38 (Minn. ct. App. 1993); Polk v State, 612 So. 2d 381 (Miss.

1993) (the trial court allowed the testimony of a game but excluded an estimate of the frequency of the accompanying population); State v Moore, 885 P.2d 457, 467, 468 (Mont. 1994) (the defendant was barred from challenging the fact that the trial court “refused to admit evidence on the basis of the statistics, but allowed the experts to testify that the RFLP and PCR test results were `compatible` with [the defendant`s DNA]”, but “if, and if so, to what extent we will admit DNA evidence without the accompanying statistical evidence in other criminal cases, will be admitted in a future case”); Rivera v State, 840 P.2d 933 (Wyo. 1992) (suggesting that best practice is not to refer to probability estimates when introducing DNA results). See, however, Springfield v. State, 860 P.2d 435 (Wyo. 1993) (probability estimate allowed). To detect possible contamination of DNA samples during collection or manipulation, DNA profiles of evidence are typically compared to those of crime scene detectives, the victim, a randomly selected person, or a DNA profile from a database. Each sample is coded and testers don`t know where the samples come from. If you are charged with a violent crime, whether you are innocent or guilty, DNA evidence presented in court can put you at ease.

DNA evidence is a powerful and useful tool for forensic investigators and lawyers, but it is not without flaws. As with any other tool used in a criminal court, the onus is on the prosecution to prove beyond a doubt that the DNA sample it found is relevant. Recommendation 6.1: Behavioural research should be conducted to identify any conditions that may lead a judge to misinterpret DNA profiling evidence and to assess the extent to which different ways of presenting expert DNA statements can reduce these misunderstandings. More recently, with the spread of PCR-based methods in the forensic field, a fourth wave of cases has occurred. The most recent cases concern attacks on the methods used to ensure the accuracy of these analyses and questions concerning the quantitative interpretation of genetic typing. Again, the underlying theory is not seriously questioned, and the ability of laboratories (at least in principle) to obtain informative results is indisputable. As in subsequent VNTR profiling cases, the defendants questioned whether the protocols used for forensic work were sufficient to prevent false positive results and questioned the procedures for estimating the frequency of genotypes detected after PCR amplification.