|Year : 2018 | Volume
| Issue : 1 | Page : 49-58
Study on problems in forensic DNA identification standardization in China and countermeasures for the same
Key Laboratory of Evidence Law and Forensic Science, Ministry of Education; Research Centre of Forensic Science Standards, China University of Political Science and Law, Beijing, China
|Date of Web Publication||30-Mar-2018|
Dr. Li Yuan
Collaborative Innovation Center of Judicial Civilization, The Key Laboratory of Scientific Evidence Under the Ministry of Education, China University of Political Science and Law, Beijing
Source of Support: None, Conflict of Interest: None
Forensic DNA analysis plays an important role in criminal cases, civil cases, missing persons' identification, and other truth-ascertaining activities. Selection of an appropriate laboratory for DNA testing, use of amplification reagents, management of database and other standardized operations, standardization of system for biological evidence in terms of sample collection, and sample analysis will improve the quality and credibility of the identification work. However, current forensic DNA standardization in China encounters some problems with respect to the development of standard and technical specification, standard documents, and DNA evidence review and acceptance. Thus, introduction and refinement of the standardization system require collective knowledge and continuous efforts. Moreover, standardization could not replace court review, and expert reports still should be cross-examined in courts.
Keywords: DNA identification, standard, technical specification
|How to cite this article:|
Yuan L. Study on problems in forensic DNA identification standardization in China and countermeasures for the same. J Forensic Sci Med 2018;4:49-58
|How to cite this URL:|
Yuan L. Study on problems in forensic DNA identification standardization in China and countermeasures for the same. J Forensic Sci Med [serial online] 2018 [cited 2022 Aug 10];4:49-58. Available from: https://www.jfsmonline.com/text.asp?2018/4/1/49/229003
| Introduction|| |
Forensic DNA analysis provides important evidence for trial and exonerates innocent persons by identifying suspects and offering clues. The field is developing rapidly. The key to ensure accuracy and reliability of forensic DNA identification, and improve fairness, is standardization of forensic DNA identification. ,, However, forensic DNA standardization has many problems at present, for example, in terms of development, training, and application of the standard documents, which more or less have an impact on the identification of DNA evidence review and acceptance.  In addition to identifying and addressing the problems, I hereby offer some suggestions and measures.
| Problems in Current Standardization Work Regarding Forensic DNA Identification|| |
Development of standard documents
At present, the standard documents with respect to forensic DNA identification could be divided into two systems: national and industrial standard documents and technical specifications. The former was developed by the National Technical Committee on Criminal Technologies of Standardization Administration of China (SAC/TC179), while the Administration of Judicial Expertise, Ministry of Justice (MOJ-AJE), developed and implemented technical specifications.
National Technical Committee on Criminal Technologies of Standardization Administration of China 179
The SAC is a public institution under the General Administration of Quality Supervision, Inspection, and Quarantine. It administers standardization work in China in a centralized manner as authorized by the State Council. SAC/TC179 is a technical organization under the Science and Technology Division, Ministry of Public Security. This organization is responsible for standardization of criminal technologies and was founded in the early 1990s with approval from the SAC. As stipulated by the Constitution of the National Standardization Technical Committee, tasks of SAC/TC179 include development of a standard system table for the area, proposing suggestions for long-term and annual plans to develop and amend national and industrial standards, and rendering assistance in development, amendment, and review of the national and industrial standards. Therefore, the national standards and public security industrial standards were initiated by the jurisdiction of SAC/TC179. Nevertheless, much work was completed by the Forensic Biological Evidence Committee of Chinese Forensic Medicine Association.
To regulate judicial expertise practice in forensic biological evidence field, speed up judicial expertise standardization, and ensure judicial expertise quality, SAC/TC179 adopted a few national standards and a series of public security industrial standards [Appendix Table 1].
Administration of Judicial Expertise, Ministry of Justice
In China, judicial expertise activities are assigned by judicial authorities according to the Decision 2.28 adopted at Session 14 of the Standing Committee of the 10 th National People's Congress on February 28, 2005. MOJ-AJE is responsible for developing and implementing judicial expertise administrative regulations and technical specifications across China.
MOJ-AJE developed the technical specifications for paternity test and four other technical specifications. The released forensic DNA identification technical specifications [Appendix Table 2] are instructive technical documents by nature, providing guidelines or information for standardization in rapidly changing technology fields. They are also special standard documents for future reference in scientific research, design, production, usage, and management. Judging from the current situation, drafting and development of the technical specifications have little to do with public security organizations and their forensic experts.
Analysis of causes as to why standard documents were developed by different organizations and problems in standardization
The standard documents were developed by different organizations because of the absence of a centralized judicial expertise administration system in China.  Previously, Decision 2.28 intended to strengthen the administration of judicial experts and judicial expertise organizations and unify China's judicial expertise administration system. It stipulated that the judicial authorities under the State Council shall be responsible for the registration and administration of nationwide judicial experts and expert organizations, while court and judicial authorities were not allowed to set up expertise organizations. Later in the same year, the Ministry of Justice released several administrative regulations as counterparts of Decision 2.28. The regulations were supposed to keep identification activities of all judicial expertise organizations within bounds. However, according to Section VII in Decision 2.28, "The expertise organizations set up by investigating departments as needed should not accept the expertise jobs entrusted by private sector." As a result, organizations involved in investigations strengthened the administration of their own identification expertise by carrying out many administrative regulations. As a result, judicial expertise came to be administered by different authorities in China, leading to identification activities not being administered in a proper and centralized manner. In addition, staff training, standard development, and application are also difficult to unify.
The standard documents were developed by different authorities, thus making their communication, promotion, training, and implementation chaotic. The industrial standards developed by SAC/TC179 are not available on the Ministry of Justice's judicial expertise website. The ministry does not require judicial expertise associations to vigorously promote and carry out training on the industrial standards among private judicial expertise organizations. On the other hand, the technical specifications have little impact on the appraisal activities of the criminal identification technical organizations under public security organs. Many police judicial experts are not aware of the existence of such technical specifications, or have no idea about how to apply them. Un-unified judicial expertise administration systems are the root cause of such chaos.
Problems in content of current standard documents
There is no specialized DNA analysis legislation in China so far, so the standard documents with respect to biological evidence authentication play an instrumental role. Standardization in this field started no more than 20 years ago and made slow progress in the early years, not being strengthened until 2008. Six industrial standards (GA/T 1162-2014, GA/T 1163-2014, GA/T382-2014, GA/T 383-2014, GA/T 1161-2014, and SF/Z JD0105002-2014) came out in 2014 to replace the two industrial standards (GB/T 21679-2008 and GA 766-2008) released in 2002; standardizing judicial expertise by providing references for DNA laboratory construction, DNA database management, test reagents, processes and methods, result interpretation, and expertise instruments. Besides, the Ministry of Justice released five technical specifications to effectively standardize duo paternity test, full-sib test, grandparent-grandchild relation identification, and single-nucleotide polymorphism genotyping, and to provide guidance for widely used sibling relation test, complementing the current standards. Although standardization of forensic biological evidence sector has made rapid progress, there are still some gaps and defects in the formulation of standardized documents, which reflects the lack of overall arrangement in the standard formulation work and needs to be further improved.
Incomplete coverage of current standard documents
Individual identification forms an important part of forensic DNA analysis. It is the process of identifying whether two or more biological evidence that emerge successively come from the same individual by testing their genetic markers. Individual identification standards are not clear. In most criminal cases, DNA analysis involves individual identification. There is no specialized standard for this in China. However, some aspects of individual identification could use the following standards as reference: the Specification for Examination of Forensic DNA Laboratory (GA/T 383-2014) providing DNA extraction methods; the Analysis and Application of the Human DNA Fluorescent STR Genotyping Result (GA/T 1163-2014) providing the requirements for STR mapping analysis and evaluation of individual identification genotyping results; the Content and Format of Forensic DNA Examination and Identification Report (GA/T 1161-2014) defining the format of and requirements for individual identification reports. However, many key aspects are not covered in these, including:
- No requirements have been suggested for maintaining effectiveness and efficiency in individual identification. In GA/T 1163-2014, it is mentioned that "detected genetic markers shall feature no <13 STR loci." However, there are nearly 60 STRs on site for forensic identification with disparate discriminatory power. For example, the discrimination power of Penta E of Han people in North China is 0.9823, while that of TPOX is only 0.7930. Different STR combinations show varying discriminatory power in unrelated individual identification, and therefore, effectiveness and efficiency of the test system should be regarded as an important index in individual identification, rather than the number of STR loci
- No minimum intensity level and threshold for the likelihood ratio in result analysis of individual identification has been introduced by GA/T 1163-2014. For instance, if DNA genotyping of an on-site sample is not consistent with that of an individual's sample, then it can be assumed that the individual did not leave behind the on-site sample. Otherwise, we cannot rule out the possibility that the sample was left behind by the individual if DNA genotyping of an on-site sample is same with that of an individual's sample. Statistical processing is needed to evaluate the intensity of the evidence in supporting the above possibility. Without a reference, it is hard for nonprofessionals to understand what the likelihood ratio value means. This may result in ambiguity in the application of the conclusions for judicial purposes
- Nonuniform expression in identification conclusions: First, when genotypes of two samples completely match, the likelihood ratio is calculated, and the conclusion that "STR genotyping of ××sample is the same as that of ××sample, the likelihood ratio ××" is issued. Such expression suffers from the flaws outlined in Section (ii) above, which will not be repeated here. Second, if the results are described as "Matched" or "Not matched" in accordance with GA/T 1163-2014, statistical analysis and deduction based on the same are missing. For the users, the ideal result is to convert the digitized statistical results into concrete opinions through statistical analysis and according to certain principles, and give objective and unbiased evidence supportive intensity.
There is no specification for low copy number test
Low copy number is relative to the DNA copy number recommended in commercial STR reagent kits.  Gill et al. define DNA copy number <100 pg as low copy number, while some scholars hold the view that this should be determined based on whether the peak threshold value detected on automatic sequencer is within limits, and hence mentioned as "any result below random threshold is analyzed as normal." Low copy number cases account for 20%-30% of the total. Ordinary tests often fail, making biological evidence authentication difficult. However, since low copy number samples often come from the crime scene and are the key to solve crime cases, testing them is inevitable. Many low copy number samples become sworn evidence later. Research shows that some extraction, reproduction, and test methods could enhance the detection rate of low copy number samples. However, incorrect genotyping may occur when detection rates are overemphasized. Therefore, the definition, test methods, mapping analysis, and result interpretation of low copy number samples need to be standardized. The laboratories need to establish proper methods to improve admissibility of low copy number evidence
The requirements for the testing of on-site samples are not clear
Whether preliminary, confirmatory, and species tests need to be carried out for suspicious material extracted on site has not been clarified in the current standards. In the opinion of many expertise organizations, DNA test is more sensitive than confirmatory test, species test, or microscopic examination. Hence, the steps prior to DNA test are often omitted, making analysis of the constituents contained in the on-site material impossible. As a result, interpretation of the evidence becomes difficult, and its content is unclear.
The paternity index calculation formula provided cannot cover all situations
Both GA/T 965-2011 and SF/Z JD0105001-2010 do not provide paternity index calculation formula in case a genetic marker does not comply with the genetic rules in a paternity test. In such cases, the judicial experts often need to calculate the paternity index by themselves. What is worse is that the calculation principles and guidance regarding the same are also absent in the two documents. As a result, wrong calculations and incorrect paternity indices are common in practice.
Repetitive and precocious standard documents
Standard development is complex and involves tireless efforts. There are many questions that need to be answered prior to standard development, including whether it is the right time to develop the standards, whether the standard overlaps other standards, and whether there are problems in the development of existing standards and technical specifications.
Discrepancy in standard documents
First, judgment criteria for paternity tests are not consistent. Paternity test is a major task in forensic DNA analysis, but the judgment criteria and conclusion expression are inconsistent among the industrial standards and technical specifications. Refer to Appendix Table 3 for details. For example, in a classic triplet paternity test, it is found that 1-2 autosomal STR loci do not follow the genetic rules, so other genetically stable DNA genetic markers with high polymorphism are added to the test; no extra inconformity is found and statistical calculation shows accumulated paternity index to be higher than 10,000. According to GA/T 965-2011, the test results could be expressed as "The man sampled is the child's biological father, which has been assured genetically, scientifically, and reasonably." But according to GA/T 1161-2014, the conclusion that "it could not be ruled out that ×× is ××'s biological father" will be issued, while technical specification SF/Z JD0105001-2010 does not provide suggestions on the expression of results in such a case. Inconsistency in conclusions leads to different probative value. The appraiser needs to pay attention to this.
Second, there is inconsistency of reporting in the same standards developed in the same period. For example, as required by GA/T 1163-2014, in genotyping results, the genotype is expressed in figures. Heterozygote figures are separated with "," (comma). Only 1 figure is marked for homozygote. The samples that were not genotyped or could not be confirmed are marked with "-". On the other hand, according to contemporary GA/T1161-2014, heterozygote genotype figures are separated with "/."
Standards surpass the current identification conditions
SF/Z JD0105002-2014 effectively standardizes full-sib test. To improve the test system's effectiveness and efficiency, generally more autosomal genetic markers need to be tested. The technical specification judges whether the samples are of unrelated individuals or full-sib based on the grade of DNA genotyping consistency (IBS) between the two individuals. As required, 19 common autosome STR loci must be tested. When additional tests are needed, 10 should be added every time to reach 29 or 39 tests. The technical specification also lists 22 complementary high-polymorphic STR loci as a choice. Since the IBS method is susceptible to STR loci polymorphism and the number of STR loci detected, the practice of limiting the STR loci for supplementation is conducive to ensuring the accuracy of identification. Moreover, the technical specification was released in 2014 when there was no satisfactory additional STR commercial reagent kit available in the Chinese market. In many test activities, AGCU 21 + 1 reagent kit was used as a supplement. Therefore, over a half of STR loci have a discriminatory power lower than 0.9 and a paternity exclusion probability <0.7, making the technical specifications inapplicable. If judgment is still made based on the threshold mentioned in the technical specification in such a case, tendentious opinions may be proven wrong.
There are many ethnic groups in China. The same ethnic group lives in different regions. Although scholars are engaged in fundamental research on STR loci group polymorphism over the last few decades, some ethnic groups' genetic information is not yet covered. Moreover, as more and more STR loci are applied to forensic expertise, basic work such as genetic polymorphism of STR in local area needs to be done. GA/T 965-2011 requires results to be calculated based on public group allele frequency or haplotype frequency and mutation rate, which is correct. However, it is not feasible in some cases at present, and so genetic data of similar groups need to be referred to in result analysis.
Problems in implementation of standard documents
Poor communication and training on standard documents
Problems of insufficient propaganda and training about issued standard documents affect the implementation of the following:
- The standard documents are not widely known. The standard documents with respect to forensic DNA analysis could be divided into two systems: national and industrial standards developed by SAC/TC179 and technical specifications developed and implemented by MOJ-AJE. The industrial standards are not well promoted among private judicial expertise organizations, while criminal investigation laboratories do not pay attention to the technical specifications
- Training regarding new normative documents is insufficient. After a batch of technical specifications is released, only the Forensic Biological Evidence Committees of Judicial Expertise Associations in very few regions engage judicial experts and their assistants in standard/technical specification communication, promotion, and interpretation. Knowledge about such normative documents for an overwhelming majority of judicial experts basically comes from self-learning. Insufficient training and varying skills of judicial experts mean that most of them could not accurately understand the major provisions and application risks outlined in the normative documents.
Arbitrariness in implementation of standard documents
Application of the standards and technical specifications is characterized by randomness in practice:
- Reference to standard documents is not unified. In some expertise instruments, the name and reference of the standards are not specified in a unified and satisfactory manner. For example, in a forensic DNA analysis, the authentication of instrument, "Anti-human seminal strip test" was recorded. The expression is not unified and satisfactory, so we do not know whether the public security industrial standard Detection Method of Human Semen PSA-Rapid Test Strip (GA 766-2008) was followed, weakening the probative force of the results
- Recommended standards are implemented optionally. Most of the current in-force national and industrial standards in the forensic DNA analysis area (except GA 765-2008 and GA 766-2008) are recommended standards, and the technical specifications are instructive documents, which are not mandatory. Many expert organizations did not implement the normative documents on their own initiative. Some analyses did not follow the standard methods
- Choose to implement industry standards or technical specifications that have a lot of arbitrariness. The normative documents feature repetition and overlapping but have different requirements. For example, while dealing with "mother-child-alleged father" paternity test, many expertise organizations follow GA/T 965-2011 and issue expertise instruments if the alleged father and child's DNA genotyping follows Mendel's laws of inheritance. If there are more than three genetic markers between the alleged father and the child that do not comply with Mendel's laws of inheritance, many appraisers would issue the report that the male is not the child's biological father in accordance with SF/Z JD0105001-2010. The latter do not need to calculate the parental index when more than three loci do not meet the genetic law. Freely choosing normative documents and failure to follow the certification and accreditation requirements and the order of precedence in the General Rules of Judicial Identification Procedure compromise the seriousness and authoritativeness of judicial expertise.
| Suggestions and Measures to Eliminate the Problems in Standardization|| |
Evidence is the basis for judicial fairness. Accuracy and reliability of expert conclusions depend on a unified and scientific judicial expertise standardization system. The standard documents regarding forensic DNA analysis authentication need to be improved and promoted. To resolve the problems in the current forensic DNA analysis, I have come up with the following suggestions and measures for discussion.
Strengthen research and review on standard documents
Train the persons involved in standard development on standardization knowledge
"Nothing is trivial with respect to standards," especially to judicial expertise related to evidence. Small unwitting problems in the standards could result in unimaginable, bad, social, and judicial consequences, for example, rejection of expertise conclusions, even "disturbance due to identification." Objectively, greater the importance that the public attaches to the standards, higher are the requirements for the standards and more difficult is their development. Standard research and development is an early activity in standardization process. Considering the problems in current standards, it is very necessary to train the staff in advance the standard research and related knowledge, help them deeply understand the current tests and examination environment, introduce satisfactory provisions using unified form and terminology, and minimize errors and risks in the standards.
Deepen preliminary study
Before a standard program is approved, its necessity, feasibility, and technical content should be investigated, researched, and analyzed.  Moreover, whether the conditions for establishing a new standard have matured in all aspects and whether they overlap with other existing standards need to be checked. Most forensic DNA analysis authentication standards are recommended standards. Whether they will be widely used in expertise activities depends to a large extent on the demand for them, their technical feasibility, compatibility, benefits, and so on. Hence, approval of standard development program should be strictly controlled to avoid "short-lived" standards.
Strictly examine rationality of drafts for approval
Forensic DNA analysis authentication standard review experts should be authoritative and influential in this profession field, and the experts from private and public security judicial expertise organizations should be engaged. Rationality review should focus on:
- Judging whether the basis for the technical provisions are sufficient: At present, the technical provisions in Chinese standards are mainly based on: mature scientific achievements, experience and lessons learned from numerous activities, the technical documents used for years, international standards, or relevant standard documents. Introduction of and appendixes to the standards submitted for approval should be analyzed carefully to judge whether the basis for the technical provisions and the test description are sufficient
- Checking whether the technical provisions are advanced: Advanced technical requirements mean that the indicators and provisions reflect the latest achievements in biological evidence technology and help improve biological evidence authentication technology and individual identification and sibling relation testing
- Judge whether the technical indicators are rational: Rational technical indicators are suitable and moderate. High indicators are difficult to meet. Rationality and feasibility should be ensured when advancement is emphasized
- Balance universality and individuality: The technical indicators should help improve biological evidence technology and generate great social benefits while leaving space and maximum freedom for technology progress. It is inappropriate to set extremely strict technical provisions. We should pay attention to universal indicators and requirements. Basic common requirements should be differentiated from variable individual technical conditions. 
Learn from sophisticated standard documents in other countries
To promote healthy development of forensic DNA analysis, many global or regional organizations overseas pay long-term attention to quality control and quality assurance of DNA tests. For example, the International Society for Forensic Genetics, American Society of Crime Laboratory Directors/Laboratory Accreditation Board, American Association of Blood Banks, FBI's Scientific Working Group on DNA Analysis Methods, and European Network of Forensic Science Institutes announce DNA test quality control requirements now and again. Keeping track of international DNA quality control practice and advanced management experience may help rapidly improve China's forensic DNA analysis and speed up standardization in China. However, when international standards or overseas quality control requirements are referred to, suitability of their technical provisions to China should be carefully checked.
Strengthen training on new standard documents
Every new standard document, having its own background and values, goes through a strict review process before it is released. After a new standard document is issued, relevant authorities should carry out promotion and training to help laboratories and judicial experts understand them as early as possible and facilitate its implementation.
Considering the problems in China's judicial expertise administration system, administrative barriers should be eliminated to facilitate inter-authority communication and exchange. Unlike jurisdiction, science has no boundary. Judicial expertise is a combination of security and public services. Judicial expertise service is provided by the government. To render better service, coordination among authorities and regions should be strengthened, and the resources should be optimized and integrated. Large-scale participation in the setup of judicial expertise public service system and provision of public products should be advocated to effectively improve the efficiency of such services. The role of Associations of Forensic Science and the Chinese Forensic Medicine Association should be given full play in standard training. We should look through the latest documents, industrial standards and technical specifications on test/examination, organization, accreditation, and laboratory certification. Continuing education for judicial experts and technicians should be provided.
Develop, amend, and improve normative documents
At present, although there are some public security industrial standards and technical specifications issued by judicial expertise authorities meeting the demand for forensic DNA analysis authentication, due to the lack of standard individual identification methods, and with the development and application of new DNA genetic markers, analytical methods, and technology platforms, new standards or technical specifications need to be developed. In a given period, a genetic marker and a test method are widely accepted by the appraiser and deemed to be the best. However, with rapid technological progress, new genetic markers or better test methods emerge and are gradually accepted by forensic DNA analysis authentication industry. Replacement of old and "the best" methods by new techniques is inevitable, so the normative documents must be amended or abolished appropriately. During application of the normative documents, we may find some shortcomings or flaws unforeseen during research and development. Competent authorities should collect recommendations through an effective feedback channel. Besides, with widespread application of the normative documents as well as the improvement of the equipment, devices, commercial reagent, and professionals' ability, recommended industrial standards stand a chance of being upgraded to mandatory or national standards (GB) after being amended and refined, and the technical specifications could be submitted for being raised to public security industrial standards.
Guide usage of recommended standards
Some expertise organizations refuse to or selectively implement the standards and technical specifications on the grounds that most public security industrial standards and all technical specifications are only recommended. According to the Standardization Law of the People's Republic of China, recommended standards are not mandatory. However, expertise organizations need to abide by and adopt the standards and technical specifications in order to ensure judicial fairness and meet the requirements for laboratory certification and accreditation. If no recommended standard is adopted, the standard it follows must be indicated as a quality commitment to the client and the parties involved, and largely, as a major means to demonstrate and improve forensic assessment quality and credibility. Specific provisions are as follows:
- Article 23 in the revised edition of the General Rules of Judicial Identification Procedure (Order 132 of the Ministry of Justice): "Judicial experts shall, in forensic appraisal activities, abide by and adopt applicable technical standards, specifications and methods in the order of priority below: (i) national standards; (ii) industrial standards and technical specifications; and (iii) technical methods recognized by most experts in the field"
- Section 4.5.17 in the Criterion for Qualification Evaluation and Accreditation of Test and Examination Organizations: "Test and examination organizations shall establish and maintain the procedures for using and confirming proper test and examination methods, including sampling, treatment, transportation, storage and preparation of to be tested/examined articles. Test and examination methods include standard and nonstandard methods, and the methods developed by the organizations." Article 2 in CQEATE: "Test and examination organizations shall adopt the methods meeting the client's demand and the test/examination requirements, including sampling methods. Priority shall be given to the methods released as international, regional or national standards. Test and examination organizations shall make sure valid versions of the standards are used"
- Article 3: "The process for the test and examination organization to develop their own test/examination methods as needed shall be well planned, which shall be completed by senior qualified staff. The plans shall be updated with the progress of the development work. Smooth communication among relevant personnel shall be ensured. When nonstandard methods are used, an agreement shall be made with the client, with respect to clarification of the client's requirements and purposes of the test. The nonstandard methods developed shall be confirmed before being used"
- Section 4.5.2 in the Guidance on Quality Control of Forensic Testing And Examination Process (CNAS-GL36) points out the order of precedence of chosen identification methods: "Identification methods shall be chosen in the following order of precedence in principle: (i) standards specified by laws and regulations; (ii) national standards; (iii) public security industrial standards; (iv) the methods designated by the client; (v) other methods: the methods published by technical organizations, guidance provided by instrument manufacturers or internal methods of expertise organizations."
Standards are rules in nature and need to be used collectively and repeatedly. Wide and repeated application of a standard generates strong influence and great benefits. Judicial expertise and laboratory certification and accreditation require standard methods to be used in identification. If a standard method is absent, nonstandard methods could be developed. However, development and implementation of the latter have limitations and need to meet the requirements. Hence, it does not make sense from a legal perspective that some expertise organizations refuse to implement recommended standards on the grounds that they are not mandatory or the standards are too many to be abided by, which is just an excuse for the subpar skills of their laboratories.
It is undeniable that there may be some flaws in recommended standards, which would be reflected after being used in many cases. Therefore, the provisions proven heavily controversial in practice and with error risks, and even the entire recommended standard, could later be ignored. Implementation of recommended standards requires confidence and voluntariness of expertise organizations, supervision by certification and accreditation agencies, and more importantly, cross-examination and acceptance of identification conclusions by courts. If an expertise instrument clearly indicates the name and reference of the standard method used, while the other does not adopt standard methods and indicates the name of used methods in an un-unified manner, the judge will prefer the former as evidence. If clients attach importance to standardization of the identification process, expertise organizations will tend to implement recommended standards, nonstandard laboratory construction, management and identification methods would be greatly reduced, discussions on whether recommended standards should be implemented would disappear, identification quality would be effectively ensured, and judicial benefits would be maximized.
| Objective Recognition of Limitations in Standardization System|| |
The standardization system could improve the quality and credibility of forensic DNA analysis authentication. Forensic DNA analysis authentication in the framework of standardization system greatly restrains subjectivity and improves objectivity and reliability. However, human intervention inevitably leads to subjective operation and judgment in authentication, for example, manual addition of sample, extra peak analysis, degraded sample analysis, and mixed sample analysis. Implementation of the standardization system would not completely avoid subjective errors. The probability of forensic DNA analysis generating satisfactory conclusions is only 65%-85%. It has been proven that an organization with accredited laboratories and certified staff once submitted flawed conclusions. Therefore, standardization does not mean that expertise reports could be accepted directly without cross-examination in court, which should not become an excuse for blind acceptance and usage of DNA evidence by judge as well as for responsibility alleviation. Standardization could never replace court review.
Of course, the standard documents are not Jacks-of-all-trades. They are only products of a certain period and are closely related to technological level, financial situations, and policies. Their functions are limited, so they cannot be distorted and magnified. They cannot standardize unpredictable and new things. Moreover, due to the limitations in current technology, not all identification purposes feature clearly defined technical indicators as standard.  Besides, during both identification and cross-examination in court, rigid usage and interpretation of the normative documents should be avoided. Cases should be analyzed separately, and their characteristics should be emphasized. Minimum standard and individuation should be well balanced.
As Chinese legislation becomes more and more complete, it is very necessary to standardize forensic DNA analysis authentication. However, standardization is a colossal project. Establishment and refinement of the system needs brainstorming, collective efforts, elimination of administrative barriers, stronger cooperation and exchange among departments/regions, improvement of testability, strict accreditation and laboratory certification, lessons from overseas system, great work in research and development, and training in and application of the normative documents. Although currently standardization of forensic DNA analysis authentication is at the evolving stage and faces a lot of problems, increased recognition of the standard system's significance; investing more human, financial, and material resources; and speeding up standardization system establishment will go a long way toward standardizing forensic DNA analysis authentication, improving laboratory management, and ensuring rule of law by evidence.
Financial support and sponsorship
This article is the result of the MOE Humanities and Social Sciences Research Youth Fund Project "Research on Issues Concerning DNA Evidence" (Register Number: 11YJC820158) and the CUPL Graduated Student Teaching Reform Project "Research on the training mode of forensic DNA practice under the background of the new procedure law" (Register Number: YJLX1637). At the same time, this article is funded by China Scholarship Council.
Conflicts of interest
There are no conflicts of interest.
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