THE O.J. SIMPSON MURDER TRIAL : Simpson Defense Presses Police Conspiracy Claim : Courts: Lawyer focuses on alleged missing blood. But chief forensic chemist says amount is exaggerated.

Turning to the central accusation in the O. J. Simpson legal team’s police conspiracy theory, a defense lawyer attempted Thursday to show that enough of Simpson’s blood sample is missing to have allowed rogue officers to taint evidence in the case.

At the same time, the attorney accused Gregory Matheson, an assistant director and chief forensic chemist at the Los Angeles Police Department’s crime lab, of misreading test results that could point to another suspect in the June 12 murders. Simpson has pleaded not guilty to killing his ex-wife Nicole Brown Simpson and her friend Ronald Lyle Goldman.

In his third day of cross-examining Matheson, Simpson lawyer Robert Blasier aggressively pressed both issues--the disputed test results and the missing-blood hypothesis. The unflappable Matheson conceded that records kept by the department do not account for all of the blood, but he made clear his skepticism about the elaborate defense conspiracy theory.

After reviewing LAPD records--and after acknowledging that a Police Department nurse said he drew about 8 milliliters of Simpson’s blood on the day after the murders--Matheson said the records do not account for what happened to about 1.5 milliliters.

That is enough, Matheson said in response to a series of hypothetical questions from Blasier, to have stained about 150 blood swatches. Swatches are small patches of cotton that are used to soak up blood and later are submitted to laboratories for testing, in this case for DNA analysis.

If blood was used to taint those swatches and someone substituted them for the ones collected at the scene of the crimes and other locations, it would compromise any later DNA test results--the same results that prosecutors consider vital in establishing that Simpson’s blood was found at the scene of the crime, and that blood containing the genetic characteristics of both victims ended up in his car and at his estate.

Still, while Matheson agreed that the LAPD records do not fully explain that missing blood, he said Blasier’s computations exaggerated the amount of blood that cannot be accounted for because they did not track blood lost when it is transferred from one vial to another.

“There’s constantly little bits going out just in the process of handling it,” Matheson said, adding that police have not traditionally kept detailed records about the volume of blood taken from suspects because disputes over the amounts never arose before the Simpson case.

As a result, he also testified that estimates of the amounts used in various tests were inexact--in fact, the nurse who drew the blood testified during the preliminary hearing that he could not be sure exactly how much he had taken.

Although the testimony about the alleged missing blood was precise and sometimes difficult to follow, involving a long series of dates and contested amounts, jurors seemed to appreciate its potential significance to the case. Even as some members of the audience were near to nodding off, jurors were listening attentively, some furiously taking notes.

But even with such important evidence at stake, the day of technical, sometimes repetitive testimony took its toll of attention spans. By day’s end, one juror seemed to be nodding off, and deputies had to caution several members of the audience to keep their eyes open.

Sources Discuss Tests

In addition to Matheson’s efforts to explain the handling of the blood, prosecutors also intend to rebut the defense’s allegation of tainted evidence by presenting results of other tests that they say will show that the test tube of Simpson’s blood could not be the source of stains sent to the laboratories.

Those tests were for the presence of a preservative known as EDTA that is added to blood when it is drawn so it does not coagulate. If EDTA is not present on the samples linked to Simpson, it would support the prosecution’s theory that the blood at the crime scene and elsewhere came directly from Simpson, not from the sample he gave to police to which the preservative was added.

Likewise, if blood samples linked to Goldman or Nicole Simpson did not contain the preservative, it would suggest that those stains came from the victims, not from the vials of blood drawn from their bodies and laced with EDTA.

Sources have said that prosecution tests of the blood drops from a trail at the crime scene showed no evidence of the preservative, but defense sources say their testing of two items did indicate that traces of the preservative were found in stains taken from a gate near the scene of the crime and on socks found in Simpson’s bedroom--socks that prosecutors say were stained with blood resembling that of Nicole Simpson.

According to one source, testing performed by the defense indicated that a conclusive result for the presence of EDTA would produce a reading of 25, while a zero would conclusively establish that no EDTA was present. That source said that the test of the stains from the gate and from the socks produced a reading of about 13.

Like so much in the Simpson case, that presages a battle of experts, who can be expected to clash over the significance of that reading.

Does it, as defense lawyers will argue, demonstrate that blood from O.J. and Nicole Simpson was used to taint certain items to frame the former football star? Or, as prosecutors maintain, does it merely reflect the fact that EDTA is widely used in commercial items and thus might appear innocently on some evidence?

Prosecutors Marcia Clark and Christopher A. Darden did not return calls seeking comment on the latest developments. Deputy Dist. Atty. Hank Goldberg in court fruitlessly objected to the defense questioning the police chemist about the significance of EDTA test results.

When Blasier attempted to ask Matheson about the possibility of EDTA on the stains from the gate and socks, Goldberg protested that the hypothetical question contained information “inconsistent with the known facts.” Judge Lance A. Ito overruled those objections, however, and Matheson testified that, hypothetically, if there were EDTA in those samples, one explanation might be that the evidence contained blood from the test tubes.

Blood Testing

Since opening statements in the murder trial, both sides have argued vigorously about blood found beneath Nicole Simpson’s fingernails. When he addressed the jury for the first time, Simpson lawyer Johnnie L. Cochran Jr. suggested that police had failed to follow up a tantalizing test result that pointed to another suspect in the case.

That result, Cochran said, indicated that blood found underneath Nicole Simpson’s fingernails contained an enzyme structure known as type B that is inconsistent with either victim or with Simpson. Under questioning from a prosecutor, Matheson delivered a technical recitation of how a blood type of BA, Nicole Simpson’s type, sometimes deteriorates into a type B. That, he said, accounts for his belief that the blood under her fingernails was her own.

That testimony was bolstered by a photograph showing her hand lying in a pool of blood, presumably her own.

But Blasier attacked Matheson’s method of reading the banding patterns that allow analysts to come to the conclusions about the enzymes in the blood. Confronting the chemist with scientific articles about how blood deteriorates, Blasier forcefully suggested that Matheson was interpreting the sometimes fuzzy enzyme photographs in a way that was intended to favor the prosecution.

At first, Matheson seemed to agree that the pattern described in the articles did not support his conclusions and acknowledged that he could not produces articles of his own supporting a different method of analysis.

But later, when prosecutor Goldberg again had the chance to question him, Matheson said the articles that the defense was relying upon did not adequately describe conditions that affected blood in the Simpson case. Specifically, one of the articles described a test run on laboratory samples that were dry and where the sources of the blood were known--conditions far different from those that afflict many crime scene investigations, including the one in the Simpson case.

Given the opportunity to explain his procedures for Goldberg, Matheson defended his conclusions and reiterated the opinion he initially gave to the jury: that while the deterioration of the blood makes it impossible for him to be absolutely sure, he remains convinced that the blood underneath Nicole Simpson’s fingernails almost certainly was her own.

That opinion, Matheson added, was bolstered by subsequent DNA tests that backed up his original suspicions.

“Mr. Matheson, are you aware that the (fingernail scrapings) were, in fact, sent out for DNA testing and came back with the result consistent with Nicole Brown?” Goldberg asked.

“That’s my understanding, yes,” Matheson replied. Although Blasier asked that Matheson’s answer be stricken from the record because Matheson did not perform any DNA tests in the case, Ito declined to take that step, remarking: “I assume we’ll get to that later.”

Conspiracy Mocked

Taking one more blast at the defense conspiracy theory Thursday, Goldberg sarcastically challenged the notion that anyone in the Police Department would want to frame Simpson and ridiculed the suggestion that moles within the lab tampered with evidence in the case.

In response to the defense insinuation that evidence could have been tampered with inside the lab’s evidence processing room, Goldberg mischievously asked a question he knew would be barred by objection.

“Is there any kind of a mechanical device or other device in the evidence processing room,” Goldberg asked, “that would warn . . . that someone was approaching and about to enter, maybe a device that might yell out: ‘Warning, someone is about to enter the evidence processing room! All evidence tampering must cease’?”

Predictably, Blasier objected. Ito, with a small shake of his head, sustained that objection.

Continuing, Goldberg posed a series of questions intended to mock the idea that officers and other employees of the Police Department, many of whom did not know each other before thex Simpson investigation, conspired to frame him for the June 12 murders.

“At any time, sir, did you ever learn that there was anyone who worked at the scientific investigations division that held or expressed any animosity toward the defendant?” Goldberg asked.

“I have not heard anything like that, no.” Matheson answered.

“Have you ever heard anything like that from Dennis Fung or Andrea Mazzola?” Goldberg asked.

Blasier objected to that question, and Goldberg followed with another that provoked an even more heated objection, this time by referring to one of the trial’s most unusual moments, the sight of Fung embracing defense attorneys as he finished up his time on the witness stand.

“Sir,” Goldberg asked, “when you were watching some of the proceedings in this case, did you in fact see any news footage of Mr. Fung shaking the hand and hugging members of the defense team?”

Although Ito rejected a request to have that question stricken from the record, he summoned attorneys from both sides to a sidebar conference, where he briefly spoke with them outside the jury’s earshot.

Criminalists Supported

During the testimony of Matheson and the two police criminalists, the conspiracy theme has consistently been accompanied by the defense’s other main line of attack--the claim that evidence in the case was handled by incompetent or poorly trained investigators and analysts.

Pursuing that line of questioning, defense attorneys grilled Fung and Mazzola at length, accusing each of mishandling evidence and of falsifying documents to cover up their mistakes and those of others. The defense has treated Matheson more gingerly, attempting to use his testimony to cast doubt on the performance of others but only rarely challenging his own performance.

Matheson has conceded some less-than-perfect work by the laboratory and others, including the Los Angeles County coroner’s office. But he has consistently downplayed the significance of problems, saying Thursday, for instance, that mistakes affecting the evidence would have shown up on controls taken from the various scenes.

Assuming that no such problems were revealed by the controls--which Goldberg suggested was the case--there was no reason to doubt the credibility of any of the evidence, Matheson said.

As the day wound to a conclusion Thursday, the LAPD veteran also offered his most stalwart defense yet of the jobs that Fung and Mazzola performed.

“Sir,” Goldberg asked, “did you ever consider . . . removing Andrea Mazzola from participating in this case?”

After an objection was overruled, Matheson answered: “No, I did not.”

“And did you ever have any questions as to the competence of the job that she performed on the crime scenes in this case?”

“No,” Matheson responded.

“And what about Mr. Fung?” the prosecutor continued.

“No,” he said again. “I had no problem with his competence on this case.”

Matheson will return to the stand this morning for what Ito hopes will be the chemist’s final day on the stand. Matheson has already spent four days testifying, but Ito has limited the questioning far more assertively than he did with previous witnesses.

Ito also denied a defense attempt to question Matheson about a knife found near Simpson’s house July 2. That knife, which the defense wanted to introduce to raise questions about whether police adequately investigated scenarios that would not implicate Simpson in the murders, was found after police repeatedly had searched the area, once with metal detectors.

Police had discounted its relevance from the start, and Ito ruled Thursday that there was no reason to believe the knife was in any way connected with the crime.

* THE SPIN

District attorney says justice system needs a shake-up. B1

(BEGIN TEXT OF INFOBOX / INFOGRAPHIC)

Dispute Over Sample

Test results on blood underneath Nicole Brown Simpson’s fingernails were inconclusive, though one possible reading suggested that the blood did not directly match blood enzyme samples from O.J. Simpson or from either of the victims. Both sides agree that the enzymes can degrade over time, but they disagree on the possible pattern of breakdown. The defense says the results show that blood belongs to some unknown person who could have committed the murders. But the prosecution says it is actually Nicole Simpson’s blood.

BLOOD PATTERNS

The test, called EAP (erythrocyte acid phosphatase), produces patterns containing various combinations of four bands, called A1, B1, A2 and B2. Nicole Simpson’s EAP type is BA, in which all four bands are present. The results of the test of blood under her fingernails contain only B1 and B2 bands, which is characteristic of type B.

The Defense Position

O.J. Simpson’s lawyers say that BA blood can degrade in only one sequence, in which the bands disappear one at a time in the order shown. In this sequence, the combination of B1 and B2 never occurs, so the defense maintains that the blood must have come from a fourth, unknown individual with EAP type B.

The Prosecution’s Explanation

Prosecutors say that the blood can degrade by a different path, in which the bands disappear in a different order, with A bands disappearing first, leaving the others behind to be tested. In this pathway, which they say is more common when the blood has not dried--as testimony has shown was the case--the combination of B1 and B2 does occur. That is why they say the blood came from Nicole Simpson.

HOW TESTING IS DONE

1. Enzymes in the blood are tested by a technique called electrophoresis. The first step is to extract the enzymes from the blood sample.

2. Enzyme samples from crime scene, along with reference samples to match them against, are placed on a sheet of glass coated with a gel. Enzymes are separated by running an electric current through the gel.

3. Samples are sprayed with a chemical that turns them blue or black.

4. The final result is a pattern of dark bands that tell which form of the enzyme is present.

Researched by THOMAS H. MAUGH II / Los Angeles Times