Luke Mitchell trial - Untested samples? FOI response

 

Claims have been made that semen samples recovered from the body of murder victim Jodi Jones, were not tested and that convicted Luke Mitchell's defence team were not made aware. 

Sandra Lean stated in an interview (Sept 2023) https://www.youtube.com/live/bnp05EIlOYg:

"One thing I think people find almost unbelievable, when I tell them this, is the vast majority of the male DNA from semen or sperm heads came back 'no reportable result'...and that's why we wanted to get some of these items re-tested. It seems unusual that there are so many tests that turned up nothing."

The spokesperson for Luke Mitchell's campaign goes on to say that 10 semen deposits found on Jodi's body were only tested as far as identifying the sample as semen. She claims they were not tested any further for DNA or to find out who the owner was (sometimes known as individualisation).

"There was a file that was marked 'not on main inventory', 'forensics, not on main inventory'...just so people understand, when items are collected, they are given a unique reference number so they can be followed through the entire investigation and through to trial and appeal if necessary. In this file, not one of the samples in there had a reference number. Not one. And we found samples in there that basically, the defence knew nothing about."

Interviewer: "And what about these ten semen deposits on Jodi's body, were they disclosed or undisclosed?"

Sandra: "They weren't disclosed as semen deposits as such...they were in a list of 'no results', great big list of 'no results' stuff and they were just in that list, so we didn't know what we got no results for, it just said 'tests brought no results'...and then when we got in to this hidden file, we realised that initially, they've tested positive for semen and then never been tested any further, just been put in to this other file and left there for 20 years."

Link to video covering other statements made by Sandra on the subject: 

https://youtu.be/sE2tVIqk63Q?si=t8_igFleJ1sK3LnP

Some questions

If the samples were in a file marked 'tests brought no results', doesn't this indicate that they were tested? Even if there was indeed the absence of a reference number, the samples were identified as semen - a stage in the process often referred to as 'confirmatory', where the use of staining and strip tests, for example, are used. If they were only tested to the stage of confirming semen, why would they be in a list titled 'tests brought not results' when the confirmation of semen is a result in itself?  Surely, 'no results' would imply that further testing was done but no results could be obtained? 

The Scottish Police Authority were asked whether they were aware of any untested samples in Jodi's case. 

They responded to say that although they did not have access to the full production list, "to assist, we are not aware of any productions submitted to forensic services in this case that have not been tested".

/https://www.spa.police.uk/publication-library/foi-2024-25-019-untested-productions-in-luke-mitchell-jody-jones-case/

So SPA would not be aware of anything on the productions list that was not submitted to forensic services for testing - however, the semen samples must have been submitted to them for testing, otherwise they could not possibly have featured on a list titled 'forensics' and 'tests brought no results'. The samples could not have been identified as semen without undergoing forensic examination. 

SPA further confirmed that if semen samples were identified, and they were all sampled, they would have been tested for DNA. 

Another FOI request has been sent with further questions. 

Some extra general information about the testing of semen

Why might semen not provide any usable results?

According to forensicresources.org, one milliliter of semen can contain between 10 and 50 million sperm cells.  This number can vary with the age of the male, and can be negatively impacted by medical conditions, genetic background, diet, and other habits such as smoking and illicit drug use. Some males in the population have a condition known as oligospermia, which defines an abnormally low sperm count. Aspermia refers to another condition where the affected male produces no sperm. Deficient sperm production may be affected by factors such as radiation and other environmental toxins, undescended testis, varicocele, trauma, drug effects or other factors. Randine Lewis, Ph.D., Male Factor Infertility, ACU-Denver Medical Article #RL-05 (2003). 

https://forensicresources.org/2011/forensic-tests-for-semen-what-you-should-know/

According to Forensic Digest.com:

The identification of one or more sperms is a conclusive proof of the presence of semen. However, there are difficulties in the identification of sperms due to several reasons.

 If a criminal is oligospermic, then his ejaculate may contain only a few sperms.

Another reason could be the condition of Aspermia where no sperms are produced by the seminiferous tubules of the testes.

If the criminal has undergone Vasectomy which is the surgical procedure for male sterilization to prevent sperm from entering into the seminal stream.

In addition to these, there may be other reasons such as sperms trapped in the clothing not extracted into the testing extracts.

Disintegration of sperms can also take place during handling of the material.

https://forensicsdigest.com/semen-as-a-forensic-evidence/#Forensic%20Importance%20of%20Semen%20as%20An%20Evidence