Forensic dna evidence interpretation pdf

It continues to serve as an invaluable resource that allows forensic scientists, technicians, molecular biologists and attorneys to use forensic DNA evidence to its greatest potential. Highlights of the second edition include: New information about PCR processes, heterozygote balance and back and forward stuttering New information on the interpretation of low template DNA, drop models and continuous models Additional coverage of lineage marker subpopulation effects, mixtures and combinations with autosomal markers This authoritative book provides a link among the biological, forensic, and interpretative domains of the DNA profiling field.

Download PDF. This latest edition is fully updated and includes current and emerging techniques in this fast-moving field. The book begins by reviewing all pertinent biology, and then provides information on every aspect of DNA analysis. This includes modern interpretation methods and contemporary population genetic models available for estimating DNA frequencies or likelihood ratios.

Following a chapter on procedures for validating databases, the text presents overviews and performance assessments of both modern sampling uncertainty methods and current paternity testing techniques, including new guidelines on paternity testing in alignment with the International Society for Forensic Genetics. A subsequent inquiry in 'As ot October In , the Model not profiles. While not addressing who such databases may include, reQuired and as such are not held electronically so are not both conventional STR DNA profiles and also mitochondrial mtDNA it spelled out procedures for sampling and the destruction of samples.

Many of profiles. In , the federal government established generally extracted from Europe the CrimTrac Agency, a law enforcement agency set up to facilitate national biological items of evidence The European Council has passed resolutions encouraging member states to such as hair, bones.

Individual states and territories Johnson and Williams, This has proved to be a slow, painstaking process which with Ireland remaining one of the last to establish a permanent database has suppressed the ability of states to cross-check DNA samples across the of DNA profiles, with legislation intended to be passed in Report on country.

ENFSI, However, despite the universal enthusiasm, there are huge gov. Every state now collects DNA from offenders, though their sampling with serious offenses. Further, in most of Europe, DNA is destroyed upon powers vary significantly. The FBI were first authorized to establish a national acquittal, altho ugh some e. This leg- pect continues to be a "risk" for future serious offending.

While variations in islation created CODIS, a supra-database consisting of DNA databases at the law governing sampling and retention are many, it may be that in the futu re, local LDIS , state SDIS , and national levels NDIS , with over public laws will come to more closely align when pressures for data sharing and har- laboratories contributing to the database.

The NDIS has two indexes: a foren- monization grow. The European Court of Human Rights has also recently sic index with profiles obtained from crime scenes and an offender index with given a dear steer on when the retention of DNA may be justified, which will profiles of individuals, these profiles consisting of 13 STR loci. A "match" on lead to modification of the UK's laws to bring them mo re into line with their European neighbors.

However, there is a risk that while scientists may attempt to answer the demands The Secretary General of Interpol recently stated that DNA profiling "has ben- of interoperability, scientific developments move faster than legal, ethical, or efited mostly the wealthiest of countries" Noble, , yet policy in this political regimes can respond.

The sending of such "personal" information area is developing rapidly and is highly ambitious. There are moves for DNA beyond jurisdictional boundaries is controversial, not least because of a lack of databases around the world to be compatible and enable searching for DNA formal procedures and legal guarantees that there will be no scope for unau- matches across borders.

The scientific techniques are also continually being thorized storage, further manipulation, or exchanges of the data. There are no refined and improved upon, with mobile DNA testing and automation also a bodies charged with oversight powers to monitor the international exchange clear aim.

However, the use of DNA technology and the relevant enabling legal of forensic DNA and no one to whom individuals may direct inquiries or com- reforms that have permitted police sampling and databasing have belatedly plaints. Such o missio ns are significant, with continued growth in agreements begun to attract critical attention from different quarters. For example, foren- to exchange forensic DNA data internatio nally and in proposals for global sic scientists have conducted research on the scientific principles underpinning databases.

There have yet to be legal rulings on whether DNA evidence fro m DNA profiling, to advance the scientific capabilities of the technique. There has another country is admissible in domestic courts, which is vital if convictions been some examination of forensic identification technologies from a socio- are to be secured.

More recently, ethical inquiries have been made bybioethicists Nuffield ETHICAL ISSUES Council on Bioethics, , while politicians have inquired into the status of forensic science in the United Kingdom generally House of Commons, The forensic use of citizens' DNA demands the highest operating standards and, more specifically, the operation and governance of surveillance technolo- in terms of accountability, security, quality assurance, and ethical standards. There are also Medical databases are strictly governed and subject to laws governing human serious reasons to suggest that the presumed "infallibility" of DNA requires rights and data protection.

However, many DNA databases held by state agen- challenging. The UK Nuffield Council of ensure security. The use of DNA is also growing among intelligence and other Bioethics have found significant room for improvement in the use of DNA and EU-wide security agencies, while rapidly evolving efforts to tackle transna- fingerprints while the National Ethics Councils of France and Portugal have tional crime entail the exchange of DNA across jurisdictions and state borders highlighted concerns and established principles for the ethical collating and e.

Indeed, the international utilization and exchange of foren- retaining ofbioinformatio n of citizens French Comite, Yet there are formidable scientific challenges with harmonization. The Nuffield Council report concluded that there must be a balance In Europe, DNA databases in member states are not compatible and cannot than the standard used in most between personal liberty and the common good.

Many now believe that the be searched against each other meaningfullyu Interpol h as also attempted to countries. There are risks with popular "no reason to fear if you are innocent" argument commonly used is not reliance upon fewer markers, a sufficient justification for the full extent of police powers.

In , Interpol's DNA demanding that there be Match prob- used in genetic research. The Oversight and management of DNA databases are becoming increasingly technoklgy now exists for abilities will be less decisive than for a full profile and should attract caution. While most uses can be clas- lyplng tllousands of SNPs from In R u Bates there was a thorough examination of issues arising in cases sified "operational," in that the use is directly related to particular police inves- a biological sample in a single in which only a partial DNA profile was found at the crime scene, concluding: automated operation.

Research could be conducted using the electronic records profiles on the database or the archived biologi- sible provided that the jury are made aware of its inherent limitations and are cal samples from which the DNA profiles have been generated.

Expanding use given a sufficient explanation to enable them to evaluate it. Advanced levels of ethical and scientific DNA samples originating from more than one person always require interpre- review are necessary because these samples are not initially obtained with con- tation, and a court has to demand evidence of a valid analysis, with interpre- sent, unlike those collected in medical settings, and remain easily traceable to tation of mixtures heavily dependent on the expert opinion of the reporting named individuals.

Profiles provided by known innocent bystanders can often be subtracted from the mixed profile to identify peaks of unknown origin, and in rape cases, special techniques may identify a male-specific profile from a vaginal swab. However, it is being more widely recognized that the crucial ele- ment for DNA databases to be effective in crime detection is the collection Low Template Number DNA of DNA samples from crime scenes, without which the DNA of individu- While DNA technology has advanced to be able to analyze ever smaller sam- als, whether serious criminals or not, is rendered meaningless.

A lot of work ples, very small samples give rise to concerns over the presentation of DNA has been undertaken on automation, with most modem laboratories now evidence. There have also "The United Kingdom has a possibility of contamination when very small amounts of material are ampli- been efforts to create mobile DNA testing capabilities, to enable rapid testing Police Elimination Database fied to obtain a profile.

Contamination, whether deliberate or accidental , is at a crime scene. This has gone so far as attemrts to create a "lab-on-a-chip " PED , which covers the a major issue which is heightened when dealing with very small samples. So far, trials of mobile Elimination Database MED , ratory team if strict preventive measures are not taken. Elimination databases DNA analysis laboratories a Forensic Response Vehicle, or FRV have demon- which has the profiles of those are maintained, which hold the profiles of potential "innocent donors" of strated the feasibility of obtai ning profiles at a crime scene, which could speed who produce the equipment DNA, and hence enable their DNA profiles to be excluded from the investiga- up investigations.

Their significant operating costs have not been justified for used In DNA analysis because tion. In the trial of Sean Hoey for a series of bombings in Northern However, there have been significant developments in laboratory methods. Each private defense, however, were able to demonstrate that the collection and storage fingerprint," which left significant room for debate, although DNA profiles still company also has databases of exhibits had not been undertaken with due diligence.

At the time of the require expert interpretation. This need becomes critical when dealing with of its staff. This was then compounded infallible. However, there are many reasons to believe that there may have been by haphazard storage and transportation of exhibits between the police and an amount of hype surrounding DNA, and our complete confidence in it may Forensic Service of Northern Ireland.

Where the science cannot be said to have been stretched as perhaps in the case of Low Template DNA, which remains controversial in Familial Searching forensic assays , there still remain instances in wh ich DNA has failed, normally Often, a speculative search on a DNA database may come up with close due to human error or corruption; lack of quality control or regulatory over- matches-often from a blood relative. This ability to find partial matches on sight; or simply the misuse or misrepresentation of DNA and its problematic the database can be used to find the blood relatives of perpetrators, which place in an adversarial legal system.

In England and Wales, there have been can provide the police with possible new investigative leads. So-called familial lapses in p olice processes, one of which saw a serial rapist and murderer evad- searching has now been used around the world to support serious crime inves- ing conviction when the DNA sample that should have been taken would have tigations.

As a result of the failure to load these profiles, it was deter- mined that crimes had gone undetected Lords Hansard, A DNA Photofit? In addition to problems detailed earlier of DNA matches not being converted The ultimate in crime-fighting intelligence tools would be for suspect DNA into detections, failing to load DNA profiles o nto databases has been a peren- found at a crime scene to be sent to the laboratory and for the scientists to then nial issue for laboratories in the United States, with huge backlogs, meaning return a "photofit" of the suspect.

The similarity of identical twins clearly dem- many laboratories taking months, if not years, to process DNA evidence. In onstrates that physical likeness is influenced by genes, and in principle, phys- Virginia, investigations in found that a quarter of the state's sex felons ical characteristics might be predictable.

Backlogs in state laboratories have become such a number of police investigations into serious crimes when they have stalled an issue that federal funding is available to laboratories, to "handle, screen, in an effort to get as much information as possible on the crime scene stain and analyze backlogged forensic DNA casework samples, as well as to improve donor.

There have been some developments in identifying redheads though DNA laboratory infrastructure and analysis capacity, so that forensic DNA sam- it cannot tell whether someone is bald or has dyed his or her hair. Perhaps even better still than a photo- their interest to build up and maintain a backlog to secure extra funds.

Since a man's Y chromosome and, most often, his surname are both inherited down the male line, there is some correlation In addition to such failures to utilize the DNA evidence available, there have between Y-chromosome markers and surnames.

For unusual surnames, the been human errors that have seen individuals wrongly implicated in crimes. Such infer- In most instances, individual forensic scientists who were dishonest or whose ences would, of course, be complicated by cases in which individuals had been work was incompetent have been discovered, although many not until years adopted or otherwise did not share the surname of their biological father. The deficiencies in the work at the Houston State Laboratory were such that the serology part of the With the significant investments made around the world in developing foren- lab was closed down and a major independent review undertaken Bromwhich, sic DNA capabilities and the continued representations of DNA as the "gold In most instances, mistakes arise from cross-contamination and misla- standard" of identification, it is not surprising that many believe DNA to be beling of samples.

These are required Yet the use of DNA has perhaps not yet reached its zenith. There remain diffi- to be updated when contamination is discovered, and they have to "follow pro- culties in convening DNA matches to actual convictions. DNA typing is now universally recognized as the standard against To improve the effectiveness of DNA databases, improved collection of DNA at which many other forensic individualization techniques are judged.

However far the laboratory processes and science may develop, the the fact that, absent fraud or an error in labelling or handling, the use of DNA is still restricted to indicating the possible presence of a person at probabilities of a false positive are quantifiable and often miniscule How that person's DNA came to be found and what this means in terms of legal liability require much more While this may be a valid representation in perfect laboratory conditions, it than a DNA "match.

So while celebrating and encouraging the effective with this powerful evidence. Thousands of offenders have been caught-many Research has not conclusively There have been several legal reforms which have enabled the use of DNA in several years after they believed they had escaped detection-while thou- ascertained hoYI often or how criminal investigations and prosecutions. The advent of DNA technology in easily this happens, nor how sands more have been eliminated as suspects in police investigations.

Men and the introduction of it into the forensic arena shortly thereafter was "innocenr transfer may result and women continue to have their wrongful convictions ovenurned and their in someone's DNA being on or revolutionary, leading to changes in policing, prosecutorial policy and proce- innocence proven with DNA tests.

The advantages of DNA then are manifold in a place where that person dures, and so on. Once the technology was further refined and improved, DNA Lake, , p. The benefits The most not. It has now become routine to take DNA from individuals and for investigators to ask and determine whether DNA evidence may play a role in solving any The power of DNA has persuaded governments internationally to create given case.

Specifically, DNA evidence may be used to speed up investigations, national DNA databases, in many cases, being prepared to share this informa- to provide intelligence to police, for the purpose of gaining cold hits, for case tion across jurisdictions and international borders in the fight against crime linkage, or as a deterrent to other possible criminals. Briody, M. Moreover, all matches n eed to be interpreted in the context of the case and Current Issues in Criminal Justice 14 2 , Australian probabilistic evidence, juries are more likely to convict when it is present, and and New Zealand Journal of Criminology 37 2 , Available at www.

Challenging Forensic Evidence? Observations on the from unresolved cases so they may be matched to future suspects. Current Issues in Crim inal Justice, tries around the world utilize these databases, including the United Kingdom, 14 3 , Forensics Under Fire. Rutgers University Press, New Brunswick. In the future, it is hoped that these databases may be compatible with French Comite consultatif national d'ethique,