Four pieces of clothing - including two pairs of blue jeans frequently mentioned by prosecutors - contain the blood of three slain children and genetic material consistent with the two men on trial for the killings, a Baltimore police DNA expert testified yesterday.
Throughout the monthlong trial of Policarpio Espinoza, 23, and Adan Canela, 18, prosecutors have alluded to evidence that connects the men to the May 27, 2004, deaths of three young relatives in Northwest Baltimore.
Yesterday, jurors heard the specifics of those links as defense attorneys worked to discredit the DNA reports.
Lynnett Redhead, a Baltimore Police Department crime lab employee, testified about her DNA analysis of such debris as skin cells collected from two left-handed work gloves and two pairs of jeans, all of which, other witnesses have said, were stained with the children's blood. The clothing was recovered from the defendants' Baltimore County home and a car they used.
Redhead's tests revealed that the debris on the inside of both gloves and one pair of jeans was consistent with Espinoza's genetic profile, and that debris inside the other jeans and one of the gloves was consistent with Canela's.
She said that she also tested a tiny droplet on a black loafer that Espinoza wore when he was arrested and found it to be consistent with the youngest victim's DNA. The substance on the shoe was never tested to determine whether it was blood, but a forensic scientist testified a few days ago that he believed that it was.
Redhead said her conclusions about the DNA were all to "a reasonable degree of scientific certainty."
Jurors heard hours of scientific testimony about the alleles that make up DNA. Redhead said she compared the alleles in DNA strands found on evidence with alleles in the DNA strands of the children, their parents and the defendants.
In cross-examination that will continue today, defense attorneys asked Redhead how certain she could be about the DNA given that the defendants are related to the children and to the children's parents and that many of the relatives in the family of illegal Mexican immigrants have similar genetic profiles. Espinoza is the children's uncle and Canela is a cousin.
DNA is the blueprint of a person's genetic makeup and it differs among everyone accept identical twins. However, family members have similarities in their DNA.
Nicholas Panteleakis, one of Espinoza's attorneys, pointed out that DNA consistent with - sometimes entirely so - the mother and father of two of the children also was present in some of the debris samples collected from the gloves and jeans.
Redhead mentioned several times that any contact with the clothing, even something as simple as turning the pants inside out after washing them, could have left a deposit of skin cells.
One of the first questions asked of Redhead by an attorney for Canela was whether she could tell how long the genetic material had been on the clothing.
"It could have been there weeks or even months?" attorney James Rhodes asked. Redhead replied "yes."
Much of Redhead's testimony was spent discussing the jeans, which could be crucial to the prosecutors' case against the men.
Assistant State's Attorney Sharon R. Holback said in her opening statement that jurors should "follow the children's blood because it will lead you to their killers."
Holback said the blood trails from the bodies of Lucero Espinoza, 8, her brother Ricardo, 9, and their male cousin, Alexis Espejo Quezada, 10, to the meat-cutting knife and cracked aluminum baseball bat that police found behind the children's apartment to two pairs of blue jeans that she said were worn by the defendants.
One dark-blue pair of No Boundaries brand jeans was recovered in the trunk of a Pontiac Grand Am that Espinoza and Canela were said to have used. Those jeans were stained in several places with the blood of the children, Redhead said.
A lighter pair of jeans found in the bedroom of the Baltimore County home where the defendants lived also was stained with the children's blood, Redhead said.
Salvatore Bianca, a forensic scientist formerly with the Baltimore Police Department, used a vacuum device that he invented to collect debris from both pairs, as well as the interior of the two bloody gloves also found inside the car. The debris likely included skin cells that were sloughed off and body oils that were deposited by the wearers of the clothing, Bianca testified.
Part of the defense strategy has been to discredit the police work in the case, which attorneys for both Espinoza and Canela said was done so hastily that the wrong men are being railroaded. Defense attorneys spent days questioning Bianca about the efficacy of his device, but the scientist said he stands by his work.
Redhead testified yesterday that debris collected by Bianca from the inside knee area of the dark jeans was consistent with Canela's DNA. And debris from several areas, such as the zipper, the waistband and inside the right knee, of the lighter jeans was consistent with Policarpio Espinoza's DNA.
But defense attorneys sought to emphasize that alleles not consistent with the slain children, their parents or the defendants also were found on several items, including the lighter pair of jeans that prosecutors say were worn by Espinoza.