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Post-Conviction Exoneration Cases in which Expert Review played a Pivotal Role

2008 Kennedy Brewer and Levon Brooks, Mississippi
Brewer was arrested in 1992 for the rape and murder of his girlfriend's 3 year old daughter Christine Jackson. The child's body was found in a creek near the Brewer home two days after she disappeared. Semen recovered from the child's body was deemed "insufficient" to test. A forensic odontologist Dr. Michael West testified numerous "bite marks" on the child were caused by Brewer. Brewer was convicted and sentenced to death in 1995.
In 2001 DNA testing of sperm DNA from the vaginal swab from the child revealed two apparent semen sources. Brewer was eliminated. If Brewer was involved, this meant there were at least three perpetrators. Brewer's conviction was vacated and he was moved off death row pending retrial where he remained for five more years.
In 2005 at FSA my review of the previous DNA testing revealed there was only one semen source. The second "contributor" was inadvertent contamination of the sperm fraction DNA with the lab's control sample. My retest of the vaginal swab confirmed this fact and produced a more extensive and unique profile for the semen source. Also at FSA, I typed about a dozen initial suspect/previous person of interest reference specimens and compared them to the sperm DNA profile. Justin Johnson, an initial suspect, was identified as the source of the semen.
When confronted with this evidence, Johnson confessed. Johnson also confessed to the murder of 3 year old Courtney Smith about 18 months earlier - for which Levon Brooks had been falsely convicted in 1992 and sentenced to life. Eerily, Brooks conviction was also based on flawed bite mark testimony by Dr. West. Both Brewer and Brooks were exonerated in 2008.


2017 Evin King, Ohio

In 1995 Evin King was convicted of the rape and murder of Crystal Hudson and sentenced to life in prison, even though he had been eliminated as the source of semen recovered from the victim's vaginal and rectal swabs. At trial the Medical Examiner testified the semen was deposited two to three days prior to the victim's death.  A forensic DNA analyst testified the semen could have been deposited as long as 16 hours prior to her death. Her body was not discovered for at least two days. The state argued the semen was not relevant to the victim's death.

In 2008 King was granted post-conviction DNA testing to attempt to determine whether DNA from the semen source might be present under the victim's fingernails. If so, such a finding should establish the relevance of the semen to the victim's death. In 2009 the Cuyahoga County Coroner's Office report revealed that DNA matching the semen was recovered from the fingernail evidence. Nevertheless, the trial court denied King's motion for relief and the appellate court affirmed the trial court's ruling in 2012.  The Ohio Supreme Court declined jurisdiction in 2013.

Later in 2013 I reviewed the testing and testimony evidence and discovered seriously discrepant observations and opinions of the medical examiner (and DNA analyst) between the autopsy report and trial testimony. This difference revealed that the number of sperm and the number of intact sperm present could be explained only by the semen being deposited at or near the time of the victim's death. The amount of sperm DNA recovered and the short persistence of foreign biology/DNA under fingernails further undermined the claim this biology was not relevant to the victim's death.

In January 2017 the Ohio Court of Appeals reversed the lower court stating "When viewed in the light of the new advanced DNA test results, this evidence suggests that the victim was raped and murdered by the same man whose DNA was found on her body. It is undisputed that this man is not King."

In April 2017 King's conviction was vacated and he was released from prison. In 2018 King was awarded $1.3 million in a settlement with the City of Cleveland and Cuyahoga County.

2000 Roy Criner, Texas
The conviction of Roy Criner included misinterpreted ABO/conventional serology findings; and similar to the Brewer case, flawed DNA testing complicated the post-conviction investigation.
Deanna Ogg was raped and murdered in Texas in 1986. The Texas criminalist testified that Criner was among 40% of the population that could not be eliminated as the source of semen found on swabs from her vagina and rectum. Criner was convicted in 1990 and was sentenced to life in prison.
Post-conviction review revealed that Ogg could have been the source of all of conventional serological genetic traits detected from her body orifice swabs. Hence, no one could be eliminated based on those findings.
Postconviction DNA testing of the swabs by the TX Department of Public Safety Austin crime lab revealed a single semen donor, and Criner was eliminated as the source. The state and courts discounted the DNA evidence as irrelevant from prior consensual sex. The state lab then tested a cigarette butt found next to the victim's body. A mixture DNA profile from at least three contributors was produced. Criner was eliminated as a contributor but the state declined to interpret the result further, so the relevance of the cigarette butt was unclear.
In 2000 I tested the cigarette butt and the rectal swab. The same sperm DNA profile - eliminating Criner - was produced from the rectal swab. A mixture of only two contributors, identified to Ogg and the semen donor, was produced from the cigarette butt. My review of the profile from the state's analysis of the cigarette butt revealed their result was compatible with Ogg, the semen donor, and a third contributor. In light of the Ogg and semen donor profiles, I was able to deduce the third person's DNA profile from the mix. When presented with these findings, the state lab identified the third contributor as the TX DPS analyst who conducted the initial testing. These findings proved the relevance of the cigarette butt and disproved the state's prior consensual sex partner theory. Criner was exonerated, and subsequently pardoned by then Governor Bush.

2016 Joseph Buffey, West Virginia
Joseph Buffey was convicted in 2002 of burglary, robbery, and the rape of an 83 year old woman in 2001. The victim stated there was only one assailant. Shortly after the crime, Buffey became a suspect. Then, after conducting DNA testing on the rape kit, the WV State Crime lab eliminated Buffey as the source of semen on the victim's vaginal swabs - even in the face of an unexpected potential minor second semen source. However, the report was not revealed to the defense until after Buffey plead guilty in a bench trial to avoid a lifetime sentence, about six weeks later. In a hearing in 2004 the state DNA analyst testified he could not conclusively eliminate Buffey as a semen contributor.
In 2011 my review of the West Virginia state testing confirmed the elimination of Buffey and revealed there was no basis for failing to eliminate him as a contributor. Post-conviction testing at FSA produced a CODIS-eligible profile from the vaginal swab (and several other specimens overlooked by the state lab) that identified the rapist. Ironically, I was obliged to testify against the actual rapist, who was convicted in 2015. Due to his confession of the burglary, Buffey was never formally exonerated of this crime.

2016 George Allen, Jr v City of St. Louis, Missouri
George Allen, Jr. was convicted in 1983 of capital murder, rape, sodomy, and burglary in the killing of a woman in St. Louis in 1982. He was sentenced to 95 years in prison. Allen initially confessed to the rape, sodomy, and murder. In the trial, a St. Louis Police Department criminalist testified that semen was found on the victim's vaginal and anal swabs, robe, crotch of her jeans, carpet near the body, a chair in the kitchen, and facial tissues in the pocket of the robe. The identification of semen was based solely on the presumptive detection of acid phosphatase, even though the SLPD lab manual specified that AP was only presumptive and identification of semen required the observation of sperm. Only the swabs were examined microscopically and no sperm were observed. The analyst testified the victim was an ABO type A secretor, Allen was a non-secretor, and he had detected A and H antigens from the body swabs and semen stains on the robe, chair, and jeans. The analyst testified the source of the semen did not possess the ABO B antigen, and that Allen could not be eliminated as the source of semen found on the victim and at the scene.
In 2003 the post-conviction investigation of this case at FSA revealed the flaws in the SLPD analyst's testing and interpretations. My examination of the victim's rectal swab, the carpet cutting, and the facial tissues failed to reveal the presence of semen. Allen was eliminated as the source of the semen on the victim's vaginal swab - later determined to be the victim's boyfriend. Other testing in 2003 revealed the semen on the victim's robe and jeans also originated from the boyfriend.
In 2010 previously undisclosed records were found that revealed the SLPD criminalist had notified investigators before Allen's arrest that the killer "probably has B or AB blood." In fact, investigators actually screened suspects by their ABO type and eliminated several who did not possess the B antigen. It was also revealed the SLPD analyst had originally authored his report stating the seminal stains came from two different persons: one type B or AB and the other an A, O, or non-secretor. In 2012 Brian Wraxall, the Chief Serologist at SERI, reviewed the available records and also pointed out the flaws in the SLPD analyst's testing and interpretations. These findings in large part, together with several other police and prosecution missteps including his coerced confession, resulted in Allen's conviction being vacated in 2012. Allen was formally exonerated in 2013.
In an affidavit in civil litigation, in addition to the serological testing flaws, my review revealed the SLPD criminalist concealed two incidents of potentially exculpatory and internally corroborative body fluid evidence and that the analyst knew his findings did not support his report and testimony. My review revealed that SLPD serologists worked in a vacuum: neither reviewed the other's work at all, both used different analytical standard operating procedures, and their supervisors were completely incapable of providing serological oversight. Further my review revealed the SLPD analyst changed his findings and report after learning Allen was a non-secretor and hence could not account for the detected B antigen. In my affidavit I recommended that all of this SLPD analyst's cases during this time period be reviewed. In 2018 the Allen estate received $14 million dollars in a pre-trial settlement from the city of St. Louis and state of Missouri.

2014 Gillard v City of Chicago
2014 Cage v City of Chicago
Larry Gillard was falsely convicted in 1982 of rape and robbery and served 27 years in prison; DNA testing in 2008 eliminated Gillard and he was exonerated in 2009. Dean Cage was falsely convicted in 1996 of child sexual abuse and served 12 years in prison; DNA testing in 2005 eliminated Cage and he was exonerated in 2008. My reviews in subsequent civil wrongful conviction litigation documented ABO testing flaws, false testimony, and the absence of internal peer review, quality control, and supervision in the Chicago Police Department crime lab. In settlements with the City of Chicago, Gillard received over $6.3 million and Cage received over $7.6 million.
Allen, Gillard, and Cage are just three of many examples of the misuse of forensic ABO blood group substance testing in government crime labs.

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