Law Enforcement use of Genealogical (DNA) Databases (Part 2).

      Following on from Part 1, and having established that the use of genealogical DNA bases as a source of direct identification evidence of a suspect in Court is not accepted by the Court, attention will now turn to how genealogical DNA databases are used by investigators to widen a pool of suspects when the pool of suspects, identified through more ‘routine’ investigative techniques, has gone dry.

     Broadly speaking, the role of an investigator, and that includes both criminal and genealogical, is to reconstruct the past.[1] That reconstruction is made by way of the use of sources, which includes people, physical evidence and records.[2] Those sources inform the investigator, and from that information, the investigator will start to develop a theory about what took place. With the aim of the investigator in mind, the investigator will focus the investigation on those sources that can provide evidence of what the investigator is seeking to determine. For a genealogical investigator, this might be seeking out documents that provide information about a date, place and cause of death of an ancestor, while for a law enforcement investigator, this will be seeking out information to identify a suspect that may have committed a crime.

     Once called to a crime scene, an investigator will seek out people (victim/s, witnesses, possible suspects etc.), documents (notes, letters, records, especially telephone records etc.) and physical evidence (tyre/tread patterns, shoeprints, DNA etc) to piece together what has taken place. Consideration will now be given, by way of a theoretical example, as to how an investigator treats two different types of physical evidence, which will lead to how genealogical DNA databases are used by law enforcement as a tool to keep an investigation ‘hot’. The physical evidence that will be considered as part of this example, will be a shoeprint found at the crime scene, and blood found at the crime scene, both established as not belonging to the victim of the crime. No suspects have been identified from inquires carried out at the crime scene.

• The first role of any law enforcement officer on arrival at a crime scene is to secure and preserve that scene in order that any physical evidence can be identified and collected.[3] In the case of a suspect’s shoeprint, the area where the print is located is taped off, and pedestrian traffic is completely removed, so that a crime scene analyst can take photographs and/or a cast of the shoeprint and the wider area where it was located. In the case of the suspects blood (DNA evidence), the blood is photographed with reference to the wider area, a sample is taken and secured in accordance with the handling of biological material, and both pieces of evidence (exhibits), are transported to the local Police Station for storage and further investigation.
• SHOEPRINT: Investigators take the photographs of the shoeprint to the local shoe store in order to identify the shoe. The owner of the store is able to identify the brand of shoe and tells the investigators that they do not stock that type of shoe, and therefore have not sold any locally.
• DNA: The DNA evidence is processed and a comparison check is carried out using the law enforcement DNA database. In this case there is no match, which suggests that the suspect in this matter has not had DNA taken before in a law enforcement capacity. It should be noted that not all offenders will have DNA profiles on the law enforcement DNA database. It should also be noted that law enforcement DNA databases process forensic DNA samples with STR (Short Tandem Repeat) Markers, which is distinct from Genealogical DNA databases, which process DNA samples with SNP (Single Nucleotide Polymorphism) Markers.[4]
• SHOEPRINT: With no suspects identified from the local shoe store, and all other inquiries exhausted, the investigators take the shoe print photographs to the manufacturer of the shoes and are advised that those shoes have sold all over the Country, although only those buyers that bought with a credit card are able to have their details supplied to investigators as cash sales do not generate any identification evidence as a credit card transaction does. At this point it should be reiterated that not all those that purchased the shoes will have their details given to investigators– the sample will be limited to credit card purchases only. It should also be noted that the handing over of personal details in this case is done by way of a production of a Warrant issued by the Court. A Warrant for the Production of evidence will ensure that the evidence obtained is not ‘tainted’, and can be produced as evidence in Court. This inquiry has resulted in a pool of suspects being identified.
• DNA: With no suspects identified from the law enforcement DNA database, and all other inquiries exhausted, the investigators take the DNA sample obtained at the crime scene to a third-party DNA processing company that can process the forensic DNA with SNP Markers, in order that it is compatible for upload to a genealogical DNA database. Once uploaded to the genealogical DNA database investigators are presented with ‘matches’ to the forensic DNA sample. These ‘matches’ are people that have uploaded their DNA to the genealogical DNA database for genealogical purposes, and are indicated as somehow ‘related’ to the suspect DNA. This inquiry has resulted in a pool of suspects being identified.
• SHOEPRINT: As the only evidence that is accepted in Court is a direct one-to-one comparison between the shoeprint at the scene and the actual shoes belonging to the suspect, it now becomes the task of the investigators to narrow down the number of suspects by way of elimination. Those that cannot be eliminated will come under closer scrutiny, for example by way of surveillance or telephone intercepts, and ultimately being spoken to and interviewed if sufficient evidence exists to implicate the suspect in the crime. When the prime suspect is identified, a Search Warrant will be applied for and executed on the home of that suspect in the hope of locating the shoes themselves. Once located, the shoes are submitted for analysis and comparison, and the comparison report, the shoeprint from the crime scene, and the shoes themselves are presented in Court as evidence, once the suspect is charged.  
• DNA: As the only evidence that is accepted in Court is a direct one-to-one comparison between the suspects DNA and the DNA located at the crime scene, and with the Courts only accepting a comparison done on the law enforcement DNA database, it now becomes the task of the investigators to narrow down the number of suspects by way of elimination in order that the suspect for the crime can be located, a DNA sample taken, and a comparison done on that DNA database. With reference to this type of elimination, it will generally fall to Genetic Genealogists to narrow down a suspect list by way of elimination due to the specialised nature of this work. Once suspects have been identified that are unable to be eliminated by the Genetic Genealogists they will come under closer scrutiny by investigators, for example by way of surveillance or telephone intercepts, and ultimately being spoken to and interviewed if sufficient evidence exists to implicate the suspect in the crime. When the prime suspect is identified, they will be placed under arrest, and once under arrest at a Police Station, a DNA sample will be taken and uploaded to the law enforcement DNA database. This DNA sample will be subjected to a one-to-one comparison with the DNA sample located at the crime scene, and the comparison report, will be presented in Court as evidence, once the suspect is charged.  

     It can be seen that the genealogical DNA database used in the example is not being used to provide direct identification evidence in Court, and is being used in a similar way to that evidence provided by the shoe manufacturer when it comes to handing over the details of those who had purchased shoes with the company; that is, to cause a pool of suspects to be created, that ultimately will be narrowed down in the hope of identifying the person responsible for the commission of the crime.

     As previously stated, this post is only providing the theory behind the use of genealogical DNA databases as a tool for suspect identification, and not, at this stage, providing endorsement, or otherwise, of their use as such.   

     Part 3 of this post will consider the degree to which actual DNA profiles within genealogical DNA databases can be used in Court as direct evidence to assist in proving the guilt of a suspect in a crime, and the implications, and whether family historians should have concerns about the way these databases are being used.

Endnotes:

[1]     James W. Osterburg and Richard H. Ward, Criminal Investigation: A Method for Reconstructing the Past, 3^rd edn., Cincinnati, Anderson Publishing, 2000, p. 349.

[2]     Ibid. p. 356.

[3]     Ibid. p. 115.

[4]     John M. Butler, Fundamentals of Forensic DNA Typing, United States of America, Academic Press, 2010, p. 7.