PASSAGE ONE OF THE DAY: "Though most results simply boosted the match statistics
beyond the CPI calculations, there were five cases in which the software
excluded the suspect—and changed the experts’ conclusions. “This demonstrated that TrueAllele could reverse erroneous matches,
and produce more convincing true matches—facilitating convictions in
languishing cases, and avoiding wrongful imprisonment,” the paper
argues. One recent case example cited is Johnnie Lee Gates—a black man who
was sentenced to die for the murder of a young white woman in Georgia in
1976. Gates has been in prison 41 years, and has attempted several
appeals. One of the latest focused on accusations of racial
discrimination on the part of prosecutors at the time of the 1977
trial—and the DNA mixtures found on ligatures used to restrain the
19-year-old victim. The racial arguments were tossed, but appeals judges
in January granted Gates a whole new trial based on TrueAllele
re-analysis of the genetic mixtures. “The adoption of probabilistic genotyping by many laboratories will
certainly prevent some of these errors from occurring in the future, but
the same laboratories that produced past errors can also now review old
cases with their new software—without additional bench work,” write
Hampikian. “It is critical that laboratories adopt procedures and
policies to do this.”
--------------------------------------------------------------
PASSAGE TWO OF THE DAY: "One recent case example cited is Johnnie Lee Gates—a black man who
was sentenced to die for the murder of a young white woman in Georgia in
1976. Gates has been in prison 41 years, and has attempted several
appeals. One of the latest focused on accusations of racial
discrimination on the part of prosecutors at the time of the 1977
trial—and the DNA mixtures found on ligatures used to restrain the
19-year-old victim. The racial arguments were tossed, but appeals judges
in January granted Gates a whole new trial based on TrueAllele
re-analysis of the genetic mixtures."
---------------------------------------------------------------
POST: "After MIX13, Labs Must Revisit DNA Mixtures Across Country, Critic Argues," by Chief Science Writer Seth Augenstein, published by Forensic Magazine on March 22, 2019.
GIST: The manual way of sorting out increasingly complex DNA mixtures can be overly simplistic—potentially leading to errors. A federal study involving more than 100 crime laboratories came to
that conclusion—six years ago. The “MIX13” study was published last year
after some public criticism, and an April 2018 report by
Forensic Magazine. Now, the chief critic of the delay in publishing MIX13 says crime
laboratories across the country should be undertaking wide-scale review
of the questionable mixture cases using the latest computer software
programs to get more accurate results. Previous conclusions backing guilty verdicts may be confirmed, but
there may also be potential innocence cases among the load, according to
the paper in the journal
Forensic Science International: Genetics. “We must go back, detect and correct our mistakes,” writes Greg
Hampikian, of Boise State University, the author. “This can all be done
without any new wet lab work.” Hampikian has been the most vocal critic of the persistence of the
use of combined probability of inclusion, or CPI—a manual computational
method to analyze complex mixtures. MIX13, conducted in 2013, asked 108 laboratories to answer five
hypothetical cases of increasing complexity. Case Five was the
culmination, involving a ski mask left behind after a bank robbery. The
mixture contained the touch DNA of four people, but initially appeared
only as a two-person mixture. The labs were given two of the four likely
contributors—plus a fifth “innocent” person who was not in the mixture
at all. Seventy percent (76 labs) of the laboratories got the wrong answer,
by including that fifth person in their analysis. Only seven
laboratories got the problem totally right, through different means.
(Four labs cited a key missing allele, and two more used a Thermo Fisher
PCR amplification data to show the fifth person could not fit). One
laboratory used the probabilistic genotyping software called TrueAllele
to come to the correct solution. The authors of MIX13, employed by the National Institutes of
Standards and Technology at the time of the work, cautioned against
assuming that CPI meant many innocent people were behind bars. One cannot draw real-world conclusions from Case Five, John Butler of NIST, one of the authors, told
Forensic Magazine last year. “We asked specific questions of labs, and part of it was a teaching
moment,” Butler said. “It wasn’t to say, here’s your error rate—because
that’s not what the purpose of that was. This was a teaching moment to
realize you can falsely include somebody with CPI.” But Hampikian and other critics see a theoretical problem which, they say, could mean miscarriages of justice. TrueAllele and other probabilistic genotyping software could be used
to conduct review of years of contested cases involving mixtures,
Hampikian argues. The DNA expert cites the example of the Virginia
Department of Forensic Science, which reviewed 144 cases using
TrueAllele. Though most results simply boosted the match statistics
beyond the CPI calculations, there were five cases in which the software
excluded the suspect—and changed the experts’ conclusions. “This demonstrated that TrueAllele could reverse erroneous matches,
and produce more convincing true matches—facilitating convictions in
languishing cases, and avoiding wrongful imprisonment,” the paper
argues. One recent case example cited is Johnnie Lee Gates—a black man who
was sentenced to die for the murder of a young white woman in Georgia in
1976. Gates has been in prison 41 years, and has attempted several
appeals. One of the latest focused on accusations of racial
discrimination on the part of prosecutors at the time of the 1977
trial—and the DNA mixtures found on ligatures used to restrain the
19-year-old victim. The racial arguments were tossed, but appeals judges
in January granted Gates a whole new trial based on TrueAllele
re-analysis of the genetic mixtures. “The adoption of probabilistic genotyping by many laboratories will
certainly prevent some of these errors from occurring in the future, but
the same laboratories that produced past errors can also now review old
cases with their new software—without additional bench work,” write
Hampikian. “It is critical that laboratories adopt procedures and
policies to do this.” Probabilistic genotyping software is increasingly being used in
laboratories nationwide. TrueAllele is used in about 10 crime labs, and
the company Cybergenetics has issued reports in 43 states, and been
approved in 20 admissibility hearings. The competitor STRmix, supplied
by a New Zealand-based company, is reportedly used by 43 federal, state
and local agencies as of a January update."
The entire post can be read at:
https://www.forensicmag.com/news/2019/03/after-mix13-labs-must-revisit-dna-mixtures-across-country-critic-argues
PUBLISHER'S
NOTE: I am monitoring this case/issue. Keep your eye on the Charles
Smith Blog for reports on developments. The Toronto Star, my
previous employer for more than twenty incredible years, has put
considerable effort into exposing the harm caused by Dr. Charles Smith
and his protectors - and into pushing for reform of Ontario's
forensic pediatric pathology system. The Star has a "topic" section
which focuses on recent stories related to Dr. Charles Smith. It can
be found at: http://www.thestar.com/topic/charlessmith. Information on "The Charles Smith Blog Award"- and its nomination process - can be found at: http://smithforensic.blogspot.com/2011/05/charles-smith-blog-award-nominations.html Please send any comments or information on other cases and issues of interest to the readers of this blog to: hlevy15@gmail.com. Harold Levy: Publisher; The Charles Smith Blog.
