DNA Expert Disputes Tampering

In a visual rebuff to the defense’s frame-up theory, a DNA expert Thursday showed jurors a slip of X-ray film that she said revealed--in black and white--how unlikely it was that anyone planted Nicole Brown Simpson’s blood on a pair of socks recovered from O.J. Simpson’s bedroom.

The film, produced during DNA analysis, showed that blood blotches on the socks matched a reference sample of blood drawn from Nicole Simpson’s body during an autopsy. Although the genetic markers matched, the two blood samples looked slightly different.

Robin Cotton, director of Cellmark Diagnostics Laboratory in Maryland, pointed out a dark smear under the genetic markers of Nicole Simpson’s reference sample--an indication, she said, that the blood had degraded substantially. The blood lifted from the socks, in contrast, looked much cleaner because it was not degraded, Cotton said.

The “discernible difference” between the two samples, she concluded, means that “it is not likely” the blood on the socks came from the reference vial. The defense has suggested that someone daubed blood from the sample onto the socks.

Cotton said the reference sample could have degraded because it was taken from Nicole Simpson’s body many hours after her death. The blood on the socks could have been in good shape, she said, if it had spurted from a fresh wound and then dried in a clean, sheltered environment. Despite the degradation, Cotton found enough DNA in both samples to call a match: Nicole Simpson, she said, was among the one in 6.8 billion people who could have produced the blood on the sock.

Cotton’s presentation in the civil case against Simpson was more graphic--and more succinct--than any of the arguments against sock tampering advanced by the prosecution in Simpson’s murder trial. It offered yet another example of how the plaintiffs, drawing lessons from the criminal trial, have launched preemptive strikes to shoot down the defense’s most potent weapons.

Simpson’s lawyers have already tried to suggest that the socks were tampered with by pointing out that several experienced criminalists examined the socks and found no blood on them--at least, not until weeks after the slayings of Nicole Simpson and her friend Ronald Lyle Goldman. They have also lined up an expert to testify that the spatter pattern on the socks suggests someone pressed the blood into the fabric. Another expert will testify that the blood on the socks contained traces of EDTA, a chemical used to preserve reference samples in test tubes.

On Thursday, Simpson’s team sought to lay the groundwork for another defense argument: that blood drops lifted from the crime scene might have been contaminated in the Los Angeles Police Department lab to such an extent that DNA tests ended up pegging them as Simpson’s. For that to happen, the real killer’s DNA would have to have degraded to the point where it was all but invisible, and then a lab technician would have to have transferred blood from Simpson’s reference sample onto all of the evidence swatches.

Under cross-examination by defense attorney Robert Blasier, Cotton agreed that such a scenario was theoretically possible.

But she vehemently rejected Blasier’s suggestion that O.J. Simpson’s blood was so clumsily handled that traces of his DNA showed up in Nicole Simpson’s reference sample. “I don’t think anyone else’s DNA is in her reference sample,” she said, after peering at an elaborate chart Blasier unveiled to try to prove that type of contamination.

Blasier’s cross-examination, while short, veered into several highly technical fields as he sought to discredit the DNA statistics linking Simpson to the crime scene.

At one point, Superior Court Judge Hiroshi Fujisaki raised his hand to catch Blasier’s attention--and pointed out that a juror was apparently nodding off. “This scintillating examination is having an effect on the jurors, or at least one of them, so I think we better take a break,” the judge said.

After the recess, Fujisaki apologized for his sarcasm. “The numbers are very important to the defense,” he told jurors. “The fact that the numbers seem to be dry sometimes . . . should not detract from [their] importance.”

Fujisaki then emphasized that all jurors and alternates must pay attention to all the evidence--an admonition he first gave a few days ago, when several jurors averted their eyes from autopsy photos. “If you find yourself drifting off, please let me know,” he said. Laughing, the jurors settled in to watch more attentively.

Thursday’s court session wrapped up with two witnesses from the state Department of Justice reporting on their DNA results. The DNA testimony is expected to conclude by Monday.