Lionel Blanks Jr. of Santa Clara is the source of semen in a brutal rape and attempted murder of a 29-year-old woman, a DNA expert testified at a preliminary hearing in Santa Clara County Superior Court in San Jose on Monday afternoon (May 16).
The victim testified last Friday she only survived because she had faked her death.
Nancy Marte, a county criminologist and DNA expert, said on Monday that she did statistical analysis on 13 of the most common DNA markers in samples taken from the victim and Blanks. The chances of anyone else having the same DNA match as Blanks are greater than 1 in 300 billion, she said.
"Unless he has an identical twin, he is the source of the semen from the vaginal swab," she said.
Marte analyzed swabs taken from the cheeks of the victim and Blanks and compared them to semen collected from the victim. She isolated non-sperm and sperm cells to differentiate the victim and assailant's DNA.
Thirteen are most commonly found in the population, according to the Federal Bureau of Investigation, she said. The analysis is in keeping with Santa Clara County Crime Lab policy, she said. She ultimately examined two additional DNA-sequence profiles, she added.
Deputy Public Defender Gilda Valeros struck hard at the county's analysis. Marte admitted Santa Clara County had devised its own policy of testing the 15 genetic markers and that its policy has never been published or peer reviewed in any scientific publication.
"The study is not commonly accepted in the scientific community. I'm not accepting any opinion that she is rendering based on an unpublished study," Valeros told Superior Court Judge Ron Del Pozzo.
But Marte explained that all of the genetic markers tested have been scientifically peer reviewed and have been accepted since 2000. They come from a national database that is widely accepted, she said.
Scientists have upped the number of markers, since two post-conviction cases in Arizona found that DNA evidence from just nine markers commonly used in rape-evidence kits produced in 1997 could not rule out that a second person might have the same DNA profile, she added.
The convicted men in the Arizona cases were later exonerated. More than 250 persons convicted of forcible rape or murders have been exonerated nationwide, according to an Innocence Project study and the National Institute of Justice, which in 2008 funded a large study of post-conviction DNA cases by the state Arizona Justice Project.
Valeros argued the county's DNA analysis can't be separated from its choice of the 13 DNA markers and its statistical calculations, which have not been published as a valid source of identification or scrutinized by scientists.
"Santa Clara County has taken the bold step of doing its own research to get DNA. … The county is applying to the laboratory interpretive guidelines" that are "more anecdotal versus a gold standard for analysis," she said.
But Marte said the use of the 13 markers is not a DNA analysis method. The county has chosen to use the most common markers, based on widely accepted, journal-published data, she said. Using 13 markers is statistically so astronomical that it rules out the possibility of finding unrelated individuals with a probable DNA match, she said.
Santa Clara County's policy isn't isolated, she added. Laboratories throughout the state can use different methods at arriving at their statistics. Some use completely different DNA sequences, but each has to be audited, she said.
Judge Del Pozzo ruled there is sufficient evidence to try Blanks, who will be arraigned on May 31, when a trial date could be set.
Blanks faces six counts that could result in life in prison if he is convicted: rape during the conviction of a kidnap, with an allegation of rape engaged in tying and binding and personally inflicting great bodily injury; sexual penetration by force; attempted murder; carjacking; robbery; and threats to commit a crime resulting in death or great bodily injury.
Del Pozzo also made additional findings. The victim had parked under lights on El Camino Real for safety and was moved to a place of "unsafety" where she would not be discovered.
"The evidence is very strong in that respect," he said.
The victim came to Palo Alto to have drinks with friends at a local bar, then became lost while driving home, she testified. She parked her Mercedes SUV under a streetlight on El Camino Real to take a nap after losing her way and driving in circles, she said.
The victim had been awake since about 5 or 5:30 a.m. that morning and became exhausted. As she slept, an assailant smashed her car window and yanked her by the neck from her vehicle. He repeatedly beat her in the head, then bound and blindfolded her and put her in the back of her car. He drove her to a remote location on school grounds in Santa Clara, where he continued to beat her, she testified. Then he raped and began strangling her, she said.
"I felt like I probably have four breaths in me, and I'm gone. I inhaled really slowly and exhaled slowly to play dead," she said. After her assailant fled, the victim was able to flag down a passing vehicle for help, she said.
This story contains 971 words.
If you are a paid subscriber, check to make sure you have logged in. Otherwise our system cannot recognize you as having full free access to our site.
If you are a paid print subscriber and haven't yet set up an online account, click here to get your online account activated.