Motion for forensic dna testing

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NO. _________________


§ IN THE _____________ COURT


§ OF


§ ____________ COUNTY, TEXAS



Now comes the Petitioner in the above styled and numbered cause, by and through his attorney of record, and pursuant to Texas Code of Criminal Procedure Articles 64.01 and 64.03, files this motion for post-conviction forensic DNA testing. Petitioner respectfully requests that this Court order Y-Chromosome (“Y-STR”) DNA testing, to be performed at a private laboratory. Petitioner would show in support of this motion the following:
Brief Statement of Facts

In _______, a jury convicted Petitioner of aggravated sexual assault of a child. The trial court judge assessed punishment, enhanced, at forty years. The victim’s eyewitness identification helped convict Petitioner.

On ______, the perpetrator approached the victim, who was walking from a friend’s house at dusk. The perpetrator led the victim to a field behind and sexually assaulted him/her. When the victim returned home, a relative called the police. When the police arrived, the victim told the police that the perpetrator descriptions, which included that he was black, bearded with a mustache, and he was wearing brown pants, blue hat, and no shirt. The police took the victim to the Hospital so that a sexual assault examination (“rape kit”) could be performed.

Biological evidence secured in relation to the sexual assault of victim consisted of that sexual assault kit, which contained the following: a vaginal swab, a vaginal smear, a swab that was unlabeled, and an anal smear. All four items from the sexual assault kit were tested for spermatozoa and seminal fluid. All tests were negative. The police department also collected victim’s clothing from the hospital police room lockbox and tested his/her shirt, skirt, underwear, and bra for biological material. The victim’s underwear contained seminal fluid, but the other items of clothing were negative for spermatozoa and seminal fluid.

The underwear’s biological material secured in relation to the offense is the basis of the challenged conviction, as required by Vernon’s Ann. Code of Criminal Procedure Art. 64.01(b). While other items in the sexual assault kit were not presumptively positive for semen or spermatozoa, male DNA other than sperm may exist and yield a genetic profile if subjected to Y-STR testing. See Orchid Cellmark's Forensic DNA Testing Services Aid In Florida Exoneration, AP Alert – Medical, May 23, 2006 (discussing the exoneration of Clarence Elkins, where experts at Orchid Cellmark used Y-STR testing to find DNA in skin cells left behind where the perpetrator had touched the victim's clothing). The evidence collected in this case was in possession of the state during the trial of the offense and was not subjected to DNA testing at that time due to an insufficient amount of seminal fluid. The forensics experts at trial were unable to link Petitioner to the physical evidence in any way.

In ___, the court granted Article 64 DNA testing in Petitioner’s case. One of the items, a stain from the victim’s underwear, tested positive for semen. Despite the presence of semen from the perpetrator, traditional autosomal DNA testing could not obtain a genetic profile to exclude Petitioner as a contributor of the sample. A newer form of DNA testing, Y-STR, can potentially produce a genetic profile of the perpetrator by analyzing markers found exclusively on the Y chromosome, which only males have. Greg Hampikian, The Future of Forensic DNA, 3 Canadian J. of Police & Security Services 5, 11 (2005). This profile can then be compared to Petitioner Y-STR profile to exclude him as the perpetrator of this crime.


As required by Art. 64.01(b)(2) of the Texas Code of Criminal Procedure, the evidence collected in this case can be subjected to a newer method of DNA testing (Y-STR testing) that provides a reasonable likelihood of results that are more accurate and probative than the results of previous DNA testing.
Autosomal testing of the evidence in this case has already been attempted and failed to produce interpretable results. Y-STR testing has the potential to obtain a male profile from the biological evidence available, and can be used to conclusively exclude Petitioner as a contributor of the biological material in this case.

Recent forensic studies validate the usefulness of Y-STR testing in situations such as Petitioner’s, where seminal fluid exists but no male profile could be obtained. This situation can occur with azospermic or vasectomized males, or in samples with few sperm where poor sampling or subjective errors by analysts result in spermatozoa being overlooked. Cassie L. Johnson et al., Analysis of Non-Suspect Samples Lacking Visually Identifiable Sperm Using a Y-STR 10-Plex, 50 J. of Forensic Sci. 1116, 1117 (2005). In one study analyzing 45 samples where standard autosomal testing did not produce probative results, 86.2% of the samples produced usable data when subjected to Y-STR testing. Id.

Y-STR testing also has a proven track record of obtaining interpretable results where autosomal tests have failed. In one recent study, Y-STR typing was performed on fifty unsolved rape cases that failed to yield a male profile after differential extraction. In 48% of the cases, sufficient male DNA existed to produce a Y-STR profile. A.F. Dekairelle & B. Hoste, Application of a Y-STR-pentaplex PCR (DYS19, DYS389I and II, DYS390 and DYS393) to sexual assault cases, 118 Forensic Sci. Int’l 122 (2001).

In another study comparing autosomal testing with Y-STR testing, partial detection of non-victim alleles (the suspect’s DNA) occurred in four cases (4%) using autosomal STRs, while Y-STR testing detected non-victim alleles in nine cases (16%). A clean male type was obtained in only 34% of cases using autosomal testing, compared with a clean male type obtained in 52% of cases using Y-STRs. Mechthild Prinz et al., Validation and casework application of a Y chromosome specific STR multiplex, 120 Forensic Sci. Int’l 177, 181 tbl.4 (2001). These studies indicate that Y-STR testing can produce probative results when traditional autosomal testing cannot.

The facts of Petitioner’s case closely resemble those cases where retesting with Y-STR provided probative genetic information. In this case, the perpetrator left behind seminal fluid, but due to a small amount of spermatozoa or a breakdown of the spermatozoa present, autosomal testing could not produce a male profile. The high percentages of successful retesting with Y-STRs reported by these studies establish a reasonable probability that retesting in this case could produce a genetic profile of the real perpetrator and exclude Petitioner.
II. Petitioner meets all of the requirements for DNA testing as required by Article 64.03 of the Code of Criminal Procedure.

In ____, this court found that Petitioner met the requirements of Article 64.03 and granted DNA testing. The requirements of Article 64.03 remain substantially the same, and the facts of Petitioner’s case still meet the statutory requirements for DNA testing:

Evidence containing biological material still exists and is in the custody of the state.
Following the completion of DNA testing, the crime laboratory returned the evidence to the police department. Texas Code of Criminal Procedure Art. 38.43 require the county and investigating agency to preserve all evidence in its custody that may contain biological material for DNA testing through the term of a convicted person’s incarceration. The evidence is in a condition that makes DNA testing possible and has been subject to a chain of custody sufficient to establish that it has not been substituted, tampered with, replaced, or altered in any material respect.

The identity of the perpetrator was and is in issue in this case.
At trial, Petitioner conviction rested on the victim’s eyewitness identification. Due to an insufficient amount of seminal fluid, the forensics experts at trial were unable to link Petitioner to the seminal fluid left by the perpetrator. In the absence of forensic evidence, the jury’s determination necessarily turned on the accuracy of the victim’s identification.

The victim’s initial description of the perpetrator was a black man with a beard and mustache wearing brown pants, blue hat, and no shirt. The night of the assault, the victim’s relative and relative’s friends searched for someone matching that description. They located a black male wearing brown pants and a striped shirt and brought him to victim’s house. After viewing the male, the victim stated that he was not his/her attacker. The next day, the victim and his/her family again went out looking for the perpetrator. Victim’s relative stopped petitioner, who was leaving a store, and the victim subsequently identified him. In victim’s initial description, he/she did not report any unusual physical characteristics about the victim. By trial, he/she recalled a scar over the perpetrator’s eye, which was consistent with Petitioner’s physical appearance. At the time he was identified, Petitioner was missing two large front teeth. Despite having talked with his/her assailant and seeing his face, the victim had not noticed his/her attacker missing two large front teeth.

Despite the enormous force that eyewitness testimony can have on juries, this/here exists a substantial body of research demonstrating that even “certain” eyewitnesses in criminal cases can be tragically mistaken. See, e.g., Samuel R. Gross et. al., Exonerations in the United States: 1989 through 2003, 95 J. Crim. L. & Criminology 523, 543 (2005) (finding that out of 328 post-conviction exonerations in the U.S. during the study period, 64% involved misidentification by one or more eyewitnesses, and that “[t]he most common cause of wrongful convictions is eyewitness misidentification.”) In the post-DNA era, individual crime victims -- sobered by proof of their honest but tragic mistakes -- have also spoken out about the errors that can befall even the most confident eyewitnesses. See Jennifer Thompson, “I Was Certain, but I Was Wrong,” The New York Times, June 18, 2000 (describing his/her identification of Ronald Cotton, who was ultimately exonerated by DNA testing).

At trial, the identity of the victim’s attacker was the central fact question in front of the jury. In opening statements, defense counsel said “I believe that the key and probably the sole issue is going to be who did it, whether it is Petitioner, or is it someone else.” Cross-examination of victim and the defense’s entire closing statement focused on the discrepancies in victim’s identification. Petitioner raised identity at trial and continues to raise it before this court.

Petitioner is prepared to establish by a preponderance of the evidence (1) that he would not have been convicted if exculpatory results had been obtained through DNA testing and (2) this request is not made to unreasonably delay the execution of sentence or administration of justice.

In support of this motion, Petitioner has sworn under oath that DNA testing would exclude him as a contributor of the biological material in this case. The current standard governing Article 64.03(a)(2)(A) only requires the petitioner to show this/here is a 51% chance that he would not have been convicted had exculpatory results been available at trial. See Smith v. State, 165 S.W.3d 361, 363-64 (Tex. Crim. App. 2005).

Petitioner’s case is the classic “silver bullet” case in which DNA testing can provide determinative proof of guilt or innocence. It was undisputed at trial that the seminal fluid collected shortly after the assault came from the perpetrator. Forensics experts attempted unsuccessfully to analyze this biological material to link Petitioner to the assault. If exculpatory results had been available at trial under these facts, even the most compelling eyewitness identification would have yielded to the power of a DNA exclusion. Weighing the scientific strength of DNA science against the fallibility of human perception, a least a 51% chance exists that Petitioner would have been acquitted.
III. Petitioner meets all of the requirements for DNA testing as required by Article 64 of the Code of Criminal Procedure and is prepared to bear the costs of private testing.

Having met all of the requirements of Article 64 of the Texas Code of Criminal Procedure, Petitioner respectfully requests that his motion be granted and DNA testing ordered. As the Texas Department of Public Safety (“DPS”) is unable to perform Y-STR testing, counsel for Petitioner agrees to bear the costs of DNA testing at a private laboratory.

Respectfully Submitted,
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