Fake paternity test results pdf

Forensic DNA Part 4

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Part 4: Uncertainties in DNA Profiling and Privacy Issues

•  Limitations of using DNA evidence: –  What DON’T DNA testing results

prove? –  How far can data be trusted? –  How and when should forensic teams

entertain alternative explanations for their data?

•  Privacy:

−  Protection of 4th amendment rights (search and seizure) in acquisition of DNA samples

−  Possible negative or unintended consequences associated with archiving DNA and maintaining large DNA sample databases

Uncertainties in DNA Profiling •  Case 1: Allele dropout

due to sample degradation (ambiguous data)

•  Case 2: The Phantom of Heilbronn (inadvertent contamination) http://en.wikipedia.org/wiki/ Phantom_of_Heilbronn

•  Case 3: Artificial DNA (nefarious contamination)

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Case 1: Allele dropout due to sample degradation (ambiguous data)

•  Often one or both alleles at a locus cannot be sequenced due to sample degradation

•  How do crime labs handle ambiguous data?

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Heterozygous alleles are well balanced

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Allele 6 amplicon has “dropped out”

Figure 6.10, J.M. Butler (2005) Forensic DNA Typing, 2nd Edition © 2005 Elsevier Academic Press

•  Crime scenes are often messy and DNA evidence is often old or has been exposed to harsh chemical environments, fire, or years of weather and sunlight by the time collected

*If this region of DNA is degraded in just one copy of the chromosome, the corresponding allele will not amplify and will not be observed in the results.

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Case 2: “The Phantom of Heilbronn” (inadvertent contamination) •  Mitochondrial DNA testing in more than

a dozen crimes (including several murders) in eastern Europe between 1993-2008 suggested a single perpetrator

•  The German government spent $18 million dollars investigating leads

•  In 2009, the DNA source was traced to a woman in a cotton swab packing plant who had handled the swabs used to collect all the associated crime scene evidence

•  An inability on the part of the investigators to entertain other possible scenarios to explain their DNA results caused an multi-year “goose chase” wasting valuable resources that might have solved other crimes

Krimsky and Simoncelli, Genetic Justice: DNA Data Banks, Criminal Investigations and Civil Liberties. Columbia University Press, 2011.

Heilbronn

Forensic DNA Part 4

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Case 3: Artificial DNA and the creation of a fabricated human DNA profile

•  A paper published in 2009 demonstrated that it is possible to prepare an artificial DNA sample in test tube

•  They made artificial DNA samples from: –  a real human DNA sample –  by piecing together DNA from a library of

known alleles •  The authors also offer a solution which is

to test DNA methylation which distinguishes between DNA from a human and artificial DNA.

•  In principle a crime scene could be contaminated with artificial DNA and the lack of authenticity would go undetected using existing forensic technology

Frumkin et al., Forensic Science International: Genetics, 2010, 4(2) pp. 95-103

Case 3: Artificial DNA

Frumkin et al., Forensic Science International: Genetics, 2010, 4(2) pp. 95-103

Fake “touch” sample

Fake saliva sample

Fake blood sample

Donor of blood for Fake blood sample (doesn’t match fake DNA found in sample)

Donor of saliva for fake saliva sample (doesn’t match fake DNA found in sample)

Forensic DNA Part 4

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Privacy Issues: protection of 4th amendment rights against “search and seizure”

The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no warrants shall issue, but upon probable cause, supported by oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.

Privacy Issues: protection of 4th amendment rights against “search and seizure”

•  Surreptitious sampling of DNA occurs when

law enforcement gathers DNA samples that have been “shed” (skin, saliva, hair follicles) without first obtaining a warrant

•  In the U.S., there is no legal protection for “abandoned” DNA samples –  e.g. DNA from saliva found on the

mouth of a beverage bottle or the butt of a cigarette

•  Several legal cases have addressed this issue, most of the ones involving DNA evidence have sided with law enforcement but other arenas of “privacy invasion” have sided with the citizen…. –  State of Washington v. Athan –  Kyllo v. United States

•  What do you think?

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Privacy Issues: possible unintended consequences

•  Early government DNA databases initially consisted of

murderers and rapists •  In 2006, President George W. Bush signed into law the “DNA Fingerprint Act of 2005” which removed an earlier provision prohibiting the upload to CODIS of arrestees who had NOT been charged or convicted of crimes

•  Since 2009, in California, a sample of DNA is taken from you if you are arrested for any felony (even if never charged or convicted)

•  Currently in the UK people arrested or detained for any crimes (…but not necessarily charged or convicted), have DNA samples taken and the UK database now contains more than 7.5% of the population

•  “Familial DNA searches” can be conducted in which DNA from crime scenes is compared against that of known felons…which sometimes eventually fingers family members of known criminals…which subjects those from larger families to greater genetic surveillance and, in essence, increases the sizes of all the databases to include innocent family members of known criminals

Krimsky and Simoncelli, Genetic Justice: DNA Data Banks, Criminal Investigations and Civil Liberties. Columbia University Press, 2011.

Privacy Issues: possible unintended consequences

“The power to assemble a permanent national DNA database of all offenders who have committed any of the crimes listed [in 18 U.S.C.] has catastrophic potential. If placed in the hands of an administration that chooses to ‘exalt order at the cost of liberty’…the database could be used to repress dissent or, quite literally, to eliminate political opposition.” -Judge Stephen R. Reinhardt in United States v. Kincade (2004).

Krimsky and Simoncelli, Genetic Justice: DNA Data Banks, Criminal Investigations and Civil Liberties. Columbia University Press, 2011.

What are some possible negative consequences of acquiring and archiving DNA samples of the population-at-large?