Posted on 11/04/2003 5:44:16 AM PST by runningbear
The Associated Press
November 3, 2003
Defense attorneys in the Laci Peterson murder case Monday challenged the type of DNA analysis done on a hair found in Scott Peterson's boat, saying the technique is too unreliable to be used in court.
Prosecutors believe the hair, found in a pair of pliers in the boat, could be from Peterson's wife, Laci, the mother-to-be who disappeared last December. An FBI crime lab supervisor testified during the preliminary hearing last week that mitochondrial DNA from the hair matched a gene swab taken earlier this year from Laci Peterson's mother, Sharon Rocha.
Defense witness William Shields, a biology professor from the State University of New York at Syracuse, testified Monday that while mitochondrial DNA testing can be useful, it is not as precise as other types of DNA testing.
Mitochondrial DNA cannot specifically identify an individual, but if compared with samples taken from a family member, it can show the statistical likelihood that a hair or other tissue came from a certain person.
Scott Peterson, 31, told police he last saw his wife on the morning before Christmas as he left to go fishing near Berkeley. He told them he returned to their Modesto home late that afternoon, shortly before family members reported Laci Peterson missing.
The bodies of Laci Peterson and her son washed ashore along the San Francisco Bay in April, about three miles from where her husband said he was fishing.
Peterson, a former fertilizer salesman, is charged with murder in the deaths of his 27-year-old wife and the baby boy she was carrying. The preliminary hearing is to determine if he will stand trial.
There is no evidence Laci Peterson was ever in the boat before her death, and prosecutors are expected to show that she did not even know about the vessel.
Mitochondrial DNA - a molecule that is much smaller than the more familiar nuclear DNA that is used to reveal a person's genetic makeup - helped identify victims of the World Trade Center attack.
It can be extracted from hair and bones when little else remains of a body.---------
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PROF RIPS LACI DNA EVIDENCE
By HOWARD BREUER
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AMBER FREY May testify today.
November 4, 2003 -- MODESTO, Calif. - A New York college professor yesterday attacked DNA evidence that prosecutors say proves Scott Peterson killed his pregnant wife Laci.
William Shields, a biology professor and DNA expert from SUNY Syracuse, told a judge that hair found in pliers in Scott's boat did not necessarily come from Laci Peterson's head and does not necessarily place the victim on his boat the day of the murder.
Pregnant Laci vanished on Christmas Eve while Scott allegedly took a solo fishing trip in San Francisco Bay.
The prosecution claims it can prove it's Laci's hair using mitochondrial DNA and comparing it with her mother, Sharon Rocha's saliva - a method which is far less foolproof than using nuclear DNA.
"It's got a much greater level of ambiguity than nuclear DNA," testified Shields.
Shields also said mitochondrial DNA could be less reliable if a subject and her mother don't share a resemblance. Laci Peterson was a brunette with an olive complexion while her mom is a fair-skinned blonde.
Scott Peterson's mistress, massage therapist Amber Frey is expected to testify this week, possibly as early as today. ...........
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Scott Peterson's attorneys challenge DNA testing
Scott Peterson's attorneys challenge DNA testing
By BRIAN MELLEY, Associated Press
Last Updated 12:35 p.m. PST Monday, November 3, 2003
MODESTO, Calif. (AP) - Defense attorneys in the Laci Peterson murder case Monday challenged the type of DNA analysis done on a hair found in Scott Peterson's boat, saying the technique is too unreliable to be used in court.
Prosecutors believe the hair, found in a pair of pliers in the boat, could be from Peterson's wife, Laci, the mother-to-be who disappeared last December. An FBI crime lab supervisor testified during the preliminary hearing last week that mitochondrial DNA from the hair matched a gene swab taken earlier this year from Laci Peterson's mother, Sharon Rocha.
Defense witness William Shields, a biology professor from the State University of New York at Syracuse, testified Monday that while mitochondrial DNA testing can be useful, it is not as precise as other types of DNA testing.
Mitochondrial DNA cannot specifically identify an individual, but if compared with samples taken from a family member, it can show the statistical likelihood that a hair or other tissue came from a certain person.
Scott Peterson, 31, told police he last saw his wife on the morning before Christmas as he left to go fishing near Berkeley. He told them he returned to their Modesto home late that afternoon, shortly before family members reported Laci Peterson missing.
The bodies of Laci Peterson and her son washed ashore along the San Francisco Bay in April, about three miles from where her husband said he was fishing.
Peterson, a former fertilizer salesman, is charged with murder in the deaths of his 27-year-old wife and the baby boy she was carrying. The preliminary hearing is to determine if he will stand trial.
There is no evidence Laci Peterson was ever in the boat before her death, and prosecutors are expected to show that she did not even know about the vessel..........
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DNA in Scott Peterson hearing becoming mainstream justice tool
Monday, November 3, 2003 12:19PM EST
DNA in Scott Peterson hearing becoming mainstream justice tool
By JIM WASSERMAN, ASSOCIATED PRESS
SACRAMENTO, Calif. (AP) - Defense attorneys in the Scott Peterson trial have called mitochondrial DNA evidence questionable science, frustrating experts and putting under a microscope what has become a mainstream tool of American justice.
Mitochondrial DNA, the genetic identification method cited last week in Peterson's preliminary hearing, has been used hundreds of times in the nation's courtrooms, helping convict the guilty and free the innocent, experts say.
Mitochondrial DNA
Special coverage from the Modesto Bee
It first appeared in a sensational 1996 Tennessee murder trial, but it has been used less frequently in California, which has higher barriers for new evidentiary techniques.
Prosecutors in the Peterson case are using mitochondrial DNA to make a case that a human hair found in pliers in Peterson's boat came from his wife, Laci, whom he is accused of killing last year.
The evidence is key to a possible prosecution argument that Peterson used the boat to ferry his pregnant wife's body to a watery grave on the day she disappeared from their Modesto home. Peterson, 31, is now charged with murder in the deaths of his 27-year-old wife and their unborn son.
An FBI lab expert said mitochondrial DNA testing can be more effective in analyzing DNA when the biological sample is small or degraded, or, as in the Peterson case, when it is a strand of hair.
But Mark Geragos, Peterson's attorney, has attacked the mitochondrial evidence, calling it the unreliable subject of "raging debate" among scientists.
Not so, said Dr. Terry Melton, chief executive officer of Mitotyping Technologies in State College, Pa., one of a handful of laboratories in the United States that extract cellular blueprints from evidence.
"It's been around for about 20 years," Melton said. "The armed forces used it to ID remains of Vietnam veterans for 10 years. Now it's being introduced quite a bit in court."
Experts say mitochondrial DNA - a tiny ring-shaped molecule that's much smaller than the more familiar nuclear DNA that reveals genetic makeup - helped identify victims of the Sept. 11, 2001, terror attack in New York. It can be extracted from hair and bones when little else remains of a body. The process takes a few days and typically costs about $2,500, Melton said.
Geragos grilled the prosecution's FBI witness about the science's weak points, prompting admissions of computer glitches and breakdowns in lab equipment. He plans to call his own witnesses to discredit forensic science techniques used to link the hair to Laci Peterson.
That argument is a long shot, analysts say, because mitochondrial DNA evidence is now typically one of many pieces of evidence used to build cases and most states have allowed it as courtroom evidence.
"It's seen as a legitimate type of science," said Fred Galves, professor at University of the Pacific's McGeorge School of Law in Sacramento.
"The more it's used and introduced into evidence, the more difficulty the defense is going to have in fighting it," said Randy Grossman, a San Diego County deputy district attorney who used it in a murder conviction last year.
Melton, who says she has testified 50 times in U.S. courtrooms since 1998 on mitochondrial DNA evidence, said challenges like Geragos' are bound to become a thing of the past "because there's simply nothing new or novel about any of the lab work."
That's not to say it's foolproof.
Galves said mitochondrial DNA from the human body cannot specifically identify an individual. Nor is it as reliable as the more familiar nuclear DNA samples, which can prove an identity based on a person's genetic fingerprint. But mitochondrial DNA, if matched with similar samples from a person's mother or sibling, can show a statistical likelihood of identification and rule out others.
"It's a piece of the puzzle, another bit of information you add to what you know about your case," Melton said.
Chattanooga, Tenn., prosecutors first used it in September 1996 to help convict Paul Ware, 27, for the rape and murder of a 4-year-old girl. Mitochondrial DNA in a hair found in the girl's throat and other hairs on her bed were successfully matched to a saliva sample from Ware.
Mitochondrial DNA also has been used to clear suspected criminals. In a 2001 Oklahoma case, it freed a man convicted of a 1981 murder by showing that a hair found in the gag stuffed in the victim's mouth did not belong to the person found guilty. Investigators had testified at the trial that the hairs were consistent with the defendant's hair, but the newer form of testing revealed otherwise.
Melton said one-third of the requests for DNA work at her Pennsylvania lab are from defense attorneys. Likewise, Galves said defense challenges like Geragos' in the Peterson case aren't entirely representative of the legal industry.
"I don't think the criminal defense bar has a real interest in poking holes in DNA," Galves said. "DNA can be their friend in a way that no other evidence can." ............
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Hair on Peterson's boat could have been contaminated, witness says
Posted on Mon, Nov. 03, 2003
Hair on Peterson's boat could have been contaminated, witness says
BY JULIA PRODIS SULEK
Knight Ridder Newspapers
MODESTO, Calif. - (KRT) - A strand of hair prosecutors hope will help convict Scott Peterson of murdering his wife and unborn son was susceptible to contamination by police officers and lab technicians, a defense witness testified Monday.
"Contamination screws up results," William Shields, a biology professor for the State University of New York, said during the fourth day of Peterson's preliminary hearing. Shields was the first witness called by the defense in the preliminary hearing, the purpose of which is to determine whether enough evidence exists for Peterson to stand trial on two murder charges in the deaths of his wife, Laci, and their unborn son.
Prosecutors say the dark hair found wound around a pair of needle-nose pliers at the bottom of Peterson's fishing boat belonged to Laci, who was eight months pregnant when she disappeared Christmas Eve. They believe the hair helps prove that Peterson killed her, transported her dead body in the boat and threw her in the San Francisco Bay, where she and her unborn son washed up separately last April.
The defense expert witness said, however, that the study of "mitochondrial DNA" used to identify the hair is imprecise and unreliable, implying the hair might not belong to Laci. Defense lawyers want to convince Stanislaus County Judge Al Girolami to prohibit the hair from being admitted into evidence.
Peterson's lawyer, Mark Geragos, has said in court papers that what was once a single strand of hair somehow became two strands by the time it reached the FBI lab for analysis. The prosecution contends the single strand could have simply broken into two parts.
Geragos contends in court papers that police officers went into the property room and opened the envelope to look at the hair - and it could have been contaminated at that point.
"Would you recommend police officers opening envelopes in property rooms to examine hairs to see if it has a root?" Geragos asked Shields, who spent all day on the witness stand.
Shields said it depended on a police officer's training in handling evidence. But he did acknowledge that at least the inspection should have been documented, especially since the hair could have been easily tainted. A second hair could have blown into the envelope, for instance, or a sweaty fingerprint could have transferred another person's DNA to the hair, he said. If the hair had a root, highly precise nuclear DNA would have been examined to identify the hair. Without it, as in this case, less precise mitochondrial data was analyzed.
Peterson, a 31-year-old fertilizer salesman, was having an affair with a Fresno massage therapist when his wife disappeared. The mistress, Amber Frey, is expected to testify later this week.
On Wednesday, Modesto Police Detective Jon Evers, who began his testimony last week, will retake the stand where he will be cross-examined by the defense about Peterson's alibi that he was fishing in the bay when his wife disappeared as well as his demeanor that night.
Also last week, prosecutors called Peterson's father to the stand as well as Laci's mother and stepsister. None of them knew that Peterson had the 14-foot aluminum Gamefisher boat - which was not kept at the home and reportedly purchased just two weeks before Laci vanished. Prosecutors are trying to prove that the slaying was premeditated and that Peterson........
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Superior Court, Stanislaus County November 3, 2003
Minute Order: Preliminary Hearing
(ie; Fourth day court provided overview)......
Prosecution spars with defense DNA expert
Prosecution spars with defense DNA expert
By JOHN COTÉ AND GARTH STAPLEY
BEE STAFF WRITERS
Last Updated: November 3, 2003, 05:43:25 PM PST
5:36 p.m., PST: Prosecutor Dave Harris sparred Monday afternoon with a defense expert over a disputed DNA testing technique in a contentious exchange marked by squabbling over definitions.
William M. Shields grew increasingly agitated with Harris in a string of exchanges about scientific terms and procedures, finally saying: Youve been doing this all along. Stop misrepresenting what Im saying.
At one point Judge Al Girolami asked Shields, a biology professor at State University in Syracuse, New York, to calm down.
Im sorry, your honor, Shields said. Im sorry.
Petersons defense team brought Shields in to testify about the reliability of mitochondrial DNA testing.
FBI lab technicians used the technique on a single hair found attached to a pair of pliers in Petersons boat.
FBI analyst Constance L. Fisher last week said the hair could not have been his but could belong to Laci Peterson. Fisher said the hair could have come from one in any 112 Caucasians.
Shields said Fisher used a faulty database to arrive at her conclusion, and recalculated that the hair could have come from one in any 11 Caucasians.
Peterson, 31, is charged with slaying his pregnant wife, Laci, and their son........
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Expert says DNA test unreliable
Expert says DNA test unreliable
Defense attorney Pat Harris, left, and DNA expert William Shields arrive at the Stanislaus County Courthouse on Monday. AL GOLUB/THE BEE
Expert William Shields testifies before Judge Al Girolami as Scott Peterson, right, and Mark Geragos listen. LAURIE McADAM/THE BEE
By JOHN COTÉ
and GARTH STAPLEY
BEE STAFF WRITERS
Last Updated: November 4, 2003, 05:37:28 AM PST
A defense expert on Monday blasted a DNA test that the FBI used on a hair found in Scott Peterson's boat, saying the technique can produce false results that are then compared against a flawed database.
In a day of testimony marked by sharp exchanges with a prosecutor, the defense expert also said mitochondrial DNA testing was susceptible to contamination because of the small sample amounts and the procedures used.
"When I sneeze, my DNA really does go into the air," said Wil-liam Shields, a professor at State University of New York at Syracuse.
"Contamination is the biggest danger to doing appropriate and reliable DNA work," Shields testified in Stanislaus County Superior Court.
The testimony came on the fourth day of Peterson's preliminary hearing on double-murder charges.
The 31-year-old fertilizer salesman from Modesto is accused of murdering his pregnant wife, Laci, and unborn son, Conner. Prosecutors are seeking the death penalty.
The human hair, found attached to a pair of needle-nose pliers, could be key physical evidence linking Laci Peterson to her husband's boat.
Prosecutors have contended in court papers that Peterson's body was in the Modesto warehouse that her husband used in his work and also in his boat. In April, passers-by found her body along the eastern shore of San Francisco Bay; prosecutors are likely to try to show that Peterson ferried her body into the water and dumped it.
But Shields testified Monday that the hair from the boat could have come from one in any nine Caucasians.
That stood in stark contrast to testimony from FBI analyst Constance L. Fisher, who said last week that the hair could not have come from Scott Peterson and may have come from his wife. Fisher said the hair could have come from one in any 112 Caucasians.
That discrepancy was due to flawed FBI calculations and an unreliable database, Shields said.
"I guarantee you," Shields said, "the way it is presented (by authorities) is biased against the defendant -- and it's wrong."
The defense is trying to show the testing technique is unreliable and evidence derived from it should be excluded from court. Judge Al Girolami is not expected to rule on the issue until after FBI scientist Dr. Bruce Budowle testifies next week.
Shields testified that FBI techniques do not sufficiently take into account evolving genetic science and could wrongly conclude that a DNA sample could not have come from a specific individual.
Under cross-examination by Senior Deputy District Attorney Dave Harris, Shields conceded that the FBI results, if accurate and not contaminated, would rule out the hair as Scott Peterson's.
Mitochondrial DNA is widely believed to be inherited maternally, meaning family members along the same maternal line will have the same mitochondrial DNA........
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(Excerpt) Read more at fox40.trb.com ...
Ugh, I need to take a shower after reading that spittle. That's the defense? Brocchini did it??? ROFL. Bye, Scottie.
Probably trying to find Greta's arm to hang on to.
"Jackie, all this defending makes me thirsty, could you hold another arm? I need that one to enjoy this delicious, refreshing Diet Coke!"
I was going to say, "I would have to see a picture of this, because lots of times I have scrunched up a rug and put in front of the door to keep the cold draft out.
Then further down the article I came across this: Scott Peterson told Evers that a dog or cat may have been playing there, Evers said.
Scott just isn't swift enough on the uptake. What I said above would have been a much better explanation.
Then I read further and see this. "Under cross-examination by defense attorney Kirk McAllister, Evers admitted that he noted nothing about the rug in his written police report, nor did he amend the report later
Don't you just love competancy?
Looking for unnamed, incoherent sources, at the bar of the Doubletree...
LOL! My thoughts exactly. She thinks she is at a film premier or something.
LOL!!
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