April 3. Reiser’s testimony was interrupted for the morning session and part of the afternoon session to accommodate the defense DNA expert, Keith Inman, who has worked with OPD criminalist at the Berkeley DOJ lab. Inman is a well qualified forensic criminalist.
The defense expert was examined by Co-counsel Richard Tamor.
Inman did not dispute that the stain on the post in the Exeter house was blood or that the identified DNA belonged to Nina and to Hans.
The blood could have come from a cut or nosebleed but not from a scratch that did not bleed. Conceivably a stain could have come from someone grabbing the post and falling. It was at least possible, in this expert’s opinion that – because there was a major contributor to the identifiable blood and a lesser one that the lesser contributor’s contribution might have come from a non-blood DNA source. [Note for argument here – in earlier testimony, apparently not disputed, it was Nina’s blood that was more prominently represented on the post.]
Inman also testified that it is not possible – given current technology – to age a particular bloodstain and that the less visible bloodstain on the sleeping bag sack might have come from “intimate contact” as well as from something more “sinister”.
The jury learned a couple of important things from this defense witness:
(1) The number of swabs that the OPD criminalist, Cavness, did or did not take from the post do not undercut the DNA identification. Whether one swab or three, Nina’s blood and Hans’s DNA were both on that post. (2) There were drops of blood on the post and drops imply, but don’t absolutely prove, splash or splatter.
On cross examination, Hora got Inman to concede that a brighter bloodstain would be fresher than an older one. [Note that everyone seems to agree that the post stain was a noticeably bright red.]
And Hora got off a beautiful question:
“If Hans Reiser got Nina Reiser’s blood on his hands and his hand touched the post or swipes the post, and part of his skin is touching the post and so is her blood, is that an activity that could leave a minor DNA donor of Hans and a major DNA donor of Nina Reiser?”
And Hora got a favorable answer, given any expert’s tendency to qualify such an answer.
“That could happen, for example if, for example, we have a richer source of DNA on his hands, like saliva perhaps, or a lot of perspiration, so I don’t think I would exclude that as a possibility. I don’t think I’ve ever thought about it quite that way. I don’t think I favor it…. but it’s certainly possible.”
That’s as good as it ever gets from an adversary expert witness.
My score from this witness is that the prosecution gained ground here. The earlier confusion engendered by Richard Tamor’s cross examination of OPD’s expert, Ms. Cavness, was cleared up, the identification of the blood was confirmed, and the jury was reminded of this evidence’s importance. That any blood spot in almost any place has a conceivable innocent explanation is always true. No expert on either side can create or dispel the contextual framework – sinister or non-sinister – the overall case provides that.