Dna Expert Says Odds Great Blood Drops Are Simpson’s

Fewer than one person in 170 million has the genetic characteristics of a blood drop found near the bodies of Ronald Lyle Goldman and Nicole Brown Simpson, and O.J. Simpson is one of the people with that rare combination, a prosecution expert in Simpson’s murder trial testified Thursday.

Blood on a sock found in his bedroom, meanwhile, only could have come from about one person in 6.8 billion - and one of those who could have been the source is Simpson’s murdered ex-wife, said Robin Cotton, director of the Maryland-based Cellmark Diagnostics DNA laboratory.

Seeking to draw the jury’s attention to the astronomical nature of those statistics, Deputy District Attorney George Clarke asked: “How many people are on earth?”

“I don’t personally know,” Cotton responded with a slight smile. “But the figure I’ve been told is about 5 billion.”

Many jurors visibly recoiled at those numbers, which only represent the conservative end of the estimates predicting the significance of so-called DNA “matches.” The odds could be even higher against someone else having left the blood in question, Cotton testified.

Some of the jurors, normally an impassive lot, literally did doubletakes as they were presented with those statistics, which prosecutors say conclusively show that Simpson, a beloved football idol, is in fact a brutal killer guilty of a double homicide. Simpson has pleaded not guilty, and he sat impassively through the DNA revelations Thursday.

Near the end of the day, his attorneys began their challenge to the DNA evidence, in part by questioning the methods used to produce the statistics introduced in court.

In contrast to Simpson’s cool demeanor, meanwhile, other trial participants seemed tightly wound on the dramatic and long-anticipated day.

Near the end of the session, a prosecutor and defense lawyer tried to shout each other down in front of the jury, an outburst that caused Superior Court Judge Lance A. Ito to slam both hands down on his desk - unlike some judges, Ito does not wield a gavel - and then to fine each of the lawyers $250. After motioning for the jury to leave, Ito made the lawyers pay immediately.

The jury did not get to see the money change hands, but it was there to witness the unveiling of the DNA test results, most of which were introduced just before the noon break.

First, jurors and Simpson were allowed to study some of the original X-rays of the DNA test results. Once they had completed those examinations, a process made comprehensible by the four-day DNA seminar that prosecutors have conducted in Ito’s court, the questioning of Cotton immediately turned to the statistics.

All the results presented Thursday figure as part of the prosecution’s case, but the tests of the crime-scene blood and the socks represent some of the government’s most powerful evidence against Simpson. Those two items of evidence bracket the prosecution’s so-called “trail of blood” with statistically powerful numbers.

And they bolster the government’s contention that Simpson was at the scene of the crimes and then tracked the victims’ blood back to his car and ultimately into his own bedroom, where the socks were discovered.

At the same time, the results presented Thursday dramatically raise the stakes for one aspect of the Simpson team’s response to the charges: his lawyers have accused police of orchestrating a conspiracy to frame their client.

Faced with DNA test results suggesting that Simpson was at the scene, the defense’s conspiracy theory assumes increasing significance as a way of explaining how the test results from Cellmark - as well as expected results from another DNA lab could so powerfully point to Simpson as the culprit.

The defense is not entirely dependent upon jurors accepting the conspiracy theory, however.

Simpson’s lawyers simultaneously have accused police of sloppy evidence-collection techniques and have suggested that they could have so badly handled samples that they contaminated them.