THE O.J. SIMPSON MURDER TRIAL

UCLA law professor Peter Arenella and Loyola University law professor Laurie Levenson offer their take on the Simpson trial. Joining them is Santa Monica defense attorney Gigi Gordon, who will rotate with other experts as the case moves forward. Today’s topic: Stirring the DNA cocktail.

PETER ARENELLA

On the prosecution: If there really is only a one in 170 million chance that someone other than O.J. Simpson could have been the source of the blood trail at Bundy, then there are only 30 other people on the planet who could have left that blood. How many of them live in Brentwood? While proof beyond a reasonable doubt cannot be quantified, such staggering odds would satisfy the prosecution’s burden if jurors reject the contamination and conspiracy theories.

On the defense: What we saw was defense by hypothetical and scientific controversy. Peter Neufeld’s cross relied on scenarios involving contamination and evidence-tampering to dilute the impact of the Bundy test results. But such a defense can backfire if the prosecution shows the jury there is little evidentiary foundation for such improbable hypotheticals. Perhaps Neufeld’s cross will pick up some steam when he focuses his attack on the problems with PCR testing.

LAURIE LEVENSON

On the prosecution: Bull’s-eye. Thursday the prosecution put on evidence, while the defense offered speculation. With astronomical numbers like one in 170 million and one in 9.7 billion, the prosecution essentially put O.J. at the scene of the crime. George Clarke and Robin Cotton did a terrific job memorializing these results in a clear chart for the jury. The question is whether jurors will reject them because of defense conspiracy and contamination claims.

On the defense: Neufeld was on the right track, but he stumbled as he tried to offer hypothetical reasons why the test results might not condemn Simpson. Neufeld is trying to throw up any obstacle he can--from bad statistics to old blood drops to degrading and disappearing DNA. He also would love to introduce other experts’ opinions without calling them, but Judge Ito has stopped him in his tracks. The defense has its work cut out for it.

GIGI GORDON

On the prosecution: The prosecution presented more damning testimony with charts that practically spelled the word ‘guilty’ in neon letters. The jurors may not have followed the science, but with each Wheel of Fortune-like flourish of the charts, the prosecution’s message was made clear. Robin Cotton may not be Vanna White, but she was looking good enough for this gig. Her professionalism and that of Clarke makes for a welcome relief.

On the defense: Neufeld went straight for the only vulnerable part of Cotton’s testimony, the statistical foundation on which her lab’s assumptions are built. Jurors must have been at least slightly surprised to hear that the prosecution’s mega-math was based on just 240 Red Cross blood donors in Detroit. It would be difficult to explain to the average person that those folks represent a random cross-section of the entire human race.

Compiled by Tim Rutten / Los Angeles Times