What Can New DNA Testing Prove? And Will Söring Ever Talk to Reporters Again?

From listening to the Small Town, Big Crime (STBC) podcast, it appears that the fearless podcasters may be contemplating a push to conduct new DNA tests on objects found at the Haysom murders crime scene (not just the evidence samples). This is something that Soering supporter Chip Harding has also called for. Wes Nance, the current Commonwealth’s attorney for Bedford County, says there would be no point in this testing, since the crime scene evidence was simply kept in boxes in a warehouse many people had access to, and is surely hopelessly contaminated by now.

Is Wes Nance right about this? He most certainly is. Here’s a brief scene from the recent 4-part documentary about the Söring case broadcast on the German channel ZDFInfo:

We see Gail Ball, attorney for Jens Söring, rummaging around in the trial evidence, holding the bloodstained housecoat Nancy Haysom died in for the camera. Now there’s Gail Ball’s DNA on that housecoat. And perhaps even the DNA of the last person Ball shook hands with, or her pets. Not to mention DNA from things the housecoat has touched in the last 35 years.

The problem with re-testing this evidence is that hundreds of people have had access to it in the 35 years since the crime. And DNA tests have become much more sensitive even in the last 10-15 years. Modern tests can detect DNA on objects simply from someone touching or breathing on them. Paradoxically, this has actually reduced the usefulness of DNA testing in heavy-contamination contexts, since any signal is going to be accompanied by larger and larger amounts of noise.

The problem, from Soering’s point of view, is that at this point, conducting DNA tests on these items is far more likely to incriminate him than exonerate him. To point suspicion away from Soering, a new DNA test of a floor tile or the housecoat would have to reveal the following

(1) a reasonably complete DNA profile (likely compiled from fragments based on statistical inferences);

(2) of one specific, potentially identifiable person;

(3) who can be proven to have deposited the DNA at the time of the murders (i.e. not while fixing a toilet or attending a dinner party);

(4) and whose DNA profile currently exists in some database for comparison, or who voluntarily gives a sample for comparison; and

(5) has no alibi.

The probability of all these factors coming together is miniscule. The most likely outcome of DNA testing random pieces of evidence is a crazy-quilt of random degraded DNA fragments which won’t yield a reasonably complete profile of any potential unknown suspect.

However, testing the new samples could potentially incriminate Soering. Let’s say you tested 50 samples, and 15 of them show DNA markers consistent with Soering but no other known visitor to the house or potential suspect. Even though you don’t have a clear profile of Soering, you might find enough Soering-specific DNA markers, scattered over various test results, to build a reasonably reliable statistical inference, along the lines of “The probability that these 15 samples all contain some partial DNA from Söring, which explains why they all have markers consistent with Soering’s, is 60,000 times likelier than the probability that they all represent errors or random contamination pointing to nobody.”

Much would depend on the specific context of exactly which items were tested and what their condition was. If bits of Soering-consistent DNA were found on a stair railing, this would be irrelevant, since Söring visited Loose Chippings a few times. But what if they were found in a bloodstain on the collar of Derek Haysom’s shirt, and in a bloodstain on the kitchen counter, and in a bloodstain on Nancy Haysom’s housecoat? It’s generally not possible to tell exactly what kind of bodily fluid or tissue a DNA sample comes from — it could be blood, saliva, skin cells, etc. But surely the fact that fragments consistent with Soering’s DNA were found in these places is highly suggestive. It’s not a slam-dunk — it could have gotten there from a sneeze, or a loud argument, transfer etc. But it would be very suspicious.

This is surely why Jens Söring never requested DNA tests on the crime-scene evidence, even as DNA technology rapidly increased in reliability and the size of the sample necessary for testing declined sharply. Now, let me put this in context. When I say the chances of results incriminating Soering are higher than results exonerating him, neither probability is high. If there’s a 5 percent chance of exoneration but a 10% chance of inculpation, then the chances of inculpation are double, but the most likely outcome remains no useful findings at all.

I’m in occasional contact with the STBC podcasters (merely as a source, not a collaborator), and have suggested that if they bring up the subject of further DNA testing with Söring, they should pay close attention to how he responds to the suggestion. My guess is that he will try to discourage it.

However, I would be surprised of Söring grants any further on-the-record interviews to the STBC journalists. They now have many questions for which Söring has no good answers. Söring has never allowed himself to be interviewed by well-informed people who could pose awkward questions. New Yorker reporter Nathan Heller recalls: “Soering, who likes to anticipate everything, tended to grow distraught when my reporting carried me into less known territory.” At the end of the latest STBC podcast, the hosts talk about someone who’s “not going to go on the record”, which “doesn’t work [for the podcasters]”, because “he’s the only one who can answer these questions”.

They don’t tell us who the unwilling subject is, but I have a pretty solid hunch. Don’t you?