Criminal law, investigative genetic genealogy, forensic genealogy, DNA
September-October 2024

Investigative Genetic Genealogy (IGG): a guide for prosecutors

By Leighton D’Antoni
Assistant Criminal District Attorney in Dallas County

Forensic investigative genetic genealogy (abbreviated FIGG, IGG, or FGG) is a groundbreaking tool in the field of criminal investigations.[1] It is revolutionizing the way DNA evidence is utilized while giving law enforcement the confidence to solve previously unsolvable violent crimes. Reflecting this confidence and enthusiasm, one investigator remarked: “I truly believe that this is the new fingerprint.”[2] It has resulted in identifying suspects in tricky cases that could not be solved any other way. A seasoned genetic genealogist explained, “In case after case, the comment is, ‘That person was never on our radar.’”[3]

            While IGG represents a game-changing advancement for law enforcement, it must be employed with responsibility and ethical consideration. Legal and privacy concerns should always be paramount. When used ethically, IGG stands as the most effective investigative method in modern criminal investigations.

What is IGG?

IGG is an innovative investigative approach that combines traditional genealogy with advanced DNA analysis to solve crimes. The technique is primarily used on cold cases, but the future of many criminal investigations that are not initially solved may be based in the world of IGG. This article will give an introductory overview of how IGG is used in criminal investigations and prosecutions.

Golden State Killer

Even after five years, it is impossible to discuss IGG without mentioning the Golden State Killer (GSK), a prolific serial killer in California during the 1970s and 1980s who was responsible for at least 13 murders and 51 home invasion rapes. This high-profile cold case was solved using IGG.

            The GSK case was the spark that ignited a transformational investigative phenomenon that is just starting to scratch the surface of its full potential. Since GSK’s arrest in 2018, IGG has helped to clear over 1,000 cases,[4] many of which involve serial offenders. At the same time, this number excludes cases in which IGG has not been confirmed by any public agency, as well as any that were not disclosed upon clearance and did not appear in the researchers’ search results.[5] The actual number of cases cleared using IGG is likely larger.

            In 2015, I started prosecuting cold cases for the Dallas County Criminal District Attorney’s Office in conjunction with the Department of Justice’s first-ever SAKI (Sexual Assault Kit Initiative) grantee class. The SAKI grant helped our office put together a full team of prosecutors, investigators, and victim advocates to focus on unsolved sexual assaults and sexual assault homicides. Ten years later, SAKI now funds grantees to investigate and prosecute any violent unsolved cold cases. SAKI, with its close relationships between its grantees and the Department of Justice (DOJ) and FBI, really are the world leaders in the IGG revolution.

            In March 2018, I read the book I’ll Be Gone in the Dark: One Woman’s Obsessive Search for the Golden State Killer, Michelle McNamara’s award-winning account of the GSK’s crimes and her quest to identify him. At the time of the book’s release, the GSK case was unsolved, and my familiarity with the case grew into an obsession. I delved into the world of crowd-sourced amateur investigations, and then unexpectedly, in April 2018, GSK was identified and arrested.

            As a cold case prosecutor, I was eager to learn how.

            By 2017, investigators had exhausted traditional methods for tracking GSK. There were no fingerprints, and GSK’s DNA did not match any profiles in law enforcement databases (CODIS). Cash rewards proved ineffective. Paul Holes, a retired cold case investigator, turned to a novel approach: a genealogy website. Holes used a DNA sample from a 1980 double murder scene attributed to GSK and ran it through GEDmatch, a public genetic database. This search led to GSK’s great-great-great grandparents. Over four months, investigators constructed a family tree, ultimately leading them to GSK, a 72-year-old grandfather, former police officer, and retired grocery store warehouse worker. He was arrested on April 24, 2018, and in August, he was charged with eight counts of first-degree murder and 13 counts of kidnapping. (Many of his earlier crimes, including several rapes, could not be charged because of California’s statute of limitations.) He pled guilty to 13 counts each of murder and kidnapping in 2020 as part of a plea bargain and admitted to numerous crimes with which he had not been formally charged. He was sentenced to life in prison (12 consecutive times over) without parole.

            The revelation that a new forensic technique combining DNA technology and genetic genealogy solved the GSK case compelled me to learn everything about IGG. I soon discovered there was widespread misinformation about it and its usage in law enforcement. Concerns about privacy and the rights of third-party individuals were potentially implicated in IGG investigations.

DOJ’s Interim Policy for Forensic Genetic Genealogy

Before proceeding with the type of forensic testing required for IGG—SNP (Single Nucleotide Polymorphisms, pronounced “snip”) testing—I should stress that law enforcement should follow the Department of Justice’s Interim Policy for Forensic Genetic Genealogical DNA Analysis and Searching.[6] It is critical for all agencies involved in an IGG investigation and prosecution to communicate with each other to ensure they are not risking federal grant funds by violating the policy, as federal law enforcement agencies and those receiving federal funding for IGG must follow the policy. Plus, its protections and procedures are in place to balance the interests and privacy rights of the public.

            The policy is clear that IGG is an investigative lead technique that should be used for identifying suspects only in “violent crimes” (murder, attempted murder, and sexual assaults) as well for identifying unknown human remains. The policy requires law enforcement to get prosecutor concurrence before using IGG. There is an exception to the “violent crimes” requirement when it concerns a matter of national security or there is an ongoing threat to public safety; these exceptions, too, require prosecutor approval.

            In the policy, “prosecutor” refers to an Assistant Attorney General, United States Attorney, state or local prosecuting attorney, or state attorney general (or his or her designee), with jurisdiction of either the crime under investigation or the location where the unidentified human remains were discovered (if those are different). This is true also when the Department of Justice and one or more state or local prosecuting authorities have concurrent jurisdiction of the crime(s) under investigation.[7]

            The DOJ Interim Policy requires that all traditional investigative methods have been exhausted and not yielded any identifiable lead or results. It requires an already uploaded STR (Short Tandem Repeat) DNA profile into CODIS that does not have a hit or match to a known offender.

            Privacy and ethical considerations are a vital component of this policy. The need to respect the privacy of individuals whose genetic data is used should always be at the forefront of law enforcement, prosecutors, defense attorneys, judges, the media, and all players in the criminal justice system. Law enforcement must use only public genetic genealogy databases that clearly state in their terms of service that law enforcement and the public at large may access their data. Informed consent from individuals who submit their DNA profiles into IGG databases is paramount to protect the important privacy rights and ethical concerns of millions of innocent third-party citizens. All uploaded personal genetic profiles and service account information shall be treated as confidential government information. Finally, law enforcement is also required to get informed consent from third parties before collecting any reference samples used for IGG.

            This policy also stipulates that IGG results serve as investigative leads only. Suspects cannot be arrested based on IGG results alone; a direct STR DNA profile comparison is necessary. Additionally, cases investigated using IGG should be entered into the FBI’s ViCAP (Violent Criminal Apprehension Program).[8]

IGG case requirements

The IGG process starts with the collection of crime scene evidence that either has biological material (e.g., a victim’s clothing) or is biological material (e.g., a vaginal swab taken from a victim during autopsy). DNA extracted from biological material can provide a genetic profile. Bodily fluids such as blood, semen, sperm, and saliva are the most common examples of bodily fluids that yield a strong STR DNA profile. Epithelial cells (from the outermost layer of skin) are also biological material from which DNA can be extracted. STR DNA is the most common type of DNA used in criminal investigations. It refers to specific sequences of DNA that consist of short segments of repeated nucleotides. STRs are highly variable among individuals, making them ideal for both genetic profiling and forensic identification (DNA fingerprinting). STR DNA has been the gold standard in court identification in criminal trials since it was first introduced in an American courtroom in 1986. Up until a few years ago, if you were talking about DNA in a criminal case, you were most likely talking about STR DNA.

            Some types of evidence may first undergo serological testing. Many times, this is dependent on the specific process of the lab testing the evidence. For our purposes, we skip ahead to the extracted DNA going through the typical STR DNA analysis flow chart of:

Quantification > Amplification > Separation > Analysis > Interpretation[9]

If there are no DNA profiles identified in the tested evidence, you are done. If the evidence contains sufficient DNA from one, two, or even more people, forensic experts can often produce a clear STR DNA profile of the person or people who left it. That STR DNA profile, sometimes called a genetic fingerprint, can provide a solid lead in a criminal investigation.[10]

            Modern STR DNA testing can identify multiple DNA profiles from a single sample, crucial in intimate samples such as those from sexual assault exams. An unknown STR DNA profile that doesn’t match any known profiles can be uploaded into CODIS. If no match is found, law enforcement may consider IGG as an investigative technique.

What is SNP testing?

Conventional DNA testing methods may not yield results when DNA is highly degraded. For example, in the World Trade Center terrorist attack, DNA of the victims was subjected to such extended periods of extreme temperature that conventional testing could not be used to identify the remains.[11] SNPs are the most common type of genetic markers found in humans. On average, every thousand bases in human DNA will contain a nucleotide site that can differ between individuals. Bases refer to the fundamental building blocks of DNA, and DNA is composed of four different types of nucleotides. Nucleotides are basic units of DNA, consisting of nitrogen, a sugar molecule, and a phosphate group. Just as DNA STRs were developed so that smaller and more degraded samples could be tested than with restriction fragment length polymorphism (RFLP), SNPs can be used to obtain results from even smaller and more degraded DNA samples than with STRs.

            IGG can examine more than half a million SNPs, which replace the STR DNA markers analyzed in traditional forensic DNA typing. These SNPs span the entirety of the human genome, allowing scientists to identify shared blocks of DNA between a forensic sample and the sample donor’s potential relatives. Recombination or reshuffling of the genome is expected as DNA from each generation is passed down, resulting in larger shared blocks of identical DNA between closer relatives and shorter blocks between more distant relatives. Due to predicted levels of recombination between generations, it is possible to analyze these blocks of genetic information and make inferences regarding potential familial relationships.[12]

            The measurement used for genetic relationships in SNP profiles is called centimorgans (cM). The closer the relationship, the more or higher the cM number will be. The human genome has about 6,800 cM. A parent-child relationship will share 50 percent of their DNA, or ~3,400 cM. If you want to learn more about shared cM and relationship levels, search online for “The Shared cM Project.” You’ll find a chart[13] that anyone doing IGG work uses all the time. It was instrumental in my training on how to build family trees and identify familial suspect pools.

Time to SNP

Once preliminary work is completed, law enforcement and prosecutors identify STR DNA evidence for submission to a SNP lab. Currently, only a few labs in the United States can perform SNP testing, and most of them are private. The very first public crime lab to offer any type of SNP testing in the United States was right here in Texas, the Center for Human Identification at The University of North Texas Health Science Center at Fort Worth.[14]

            The crime lab that performs the original STR DNA testing will determine whether a DNA extract exists. If it does, the lab will need to quantify (“quant”) the sample to ensure there is enough DNA for the SNP lab. It may be that another DNA extraction from the original STR DNA sample or evidence is needed. In those cases, it is always best to have the original STR DNA lab perform the extract before sending it to the SNP lab. This is especially true if that lab is CODIS accredited. When the SNP lab receives the evidence, it will analyze the collected DNA to create a detailed genetic SNP profile of the unknown suspect. As previously mentioned, the profile is much more comprehensive than those used in traditional forensic DNA databases.

            One more thought on SNP testing and the labs that perform it: Not all SNP testing labs use the same testing technique, and each technique tests a different number of SNP markers. Currently, the three most common types of SNP testing methods are Whole Genome Sequencing, Microarray, and Kintelligence. Whole Genome Sequencing is best for low-level and degraded DNA. The commercial kit companies (23andMe and MyHeritage) all use Microarray. Kintelligence targets the lowest level in its SNP profiles of the three (10,230 SNP markers) but it is said to be explicitly curated for forensic kinship use with the ForenSeq Kintelligence Kit. Kintelligence also claims to be the only sequencing-based assay designed for IGG.[15] If you are involved in an IGG investigation, you should at least be aware of what method may be or was used for your case. Certain evidence may benefit from the higher marker level of testing that comes with using Whole Genome Sequencing and Microarray.

Upload and tree build

Once a SNP profile is created, that profile is sent to the law enforcement agency investigating the case to be uploaded into a public, searchable genetic database. GEDmatch is by far the most widely used; it is marketed as offering “comprehensive solutions for genetic genealogy and family tree search,” and it allows users to compare their DNA test results with those of other people across the globe. It also lets users “opt in” to the Genetic Witness Program, where law enforcement can upload unknown DNA data to GEDmatch to find relatives of the unknown donor.[16] Such databases contain the DNA of millions of individuals, almost all of whom have voluntarily submitted their genetic information in the hope of tracing their ancestry or finding biological relatives, and law enforcement never has access to users’ raw DNA data.

            Law enforcement or genetic genealogists then evaluate the shared genetic variations in the suspect’s SNP profile to start building a family tree. The number of SNP variations shared between individuals can help approximate the genetic distance between them. This data is used to determine the degree of relation and placement within the family tree.

            Rarely will law enforcement be able to identify a suspect based on the initial upload of a SNP profile into a public database, but it does happen. In June 2020, I vividly remember being at my son’s baseball game on a Saturday morning when I got a call from FBI Special Agent Randy White. Randy leads the FBI’s IGG Team in Dallas, and I started working with him on IGG cases in late 2019. Up until that Saturday, we had not identified a suspect using IGG for a Dallas County case. We had submitted evidence on some cases for SNP testing and FBI had been building trees, but no concrete results pointing to a specific suspect in those cases. I knew that the Friday before, Randy and his team had gotten the SNP results back from a case we had just submitted, but I wasn’t expecting to hear anything back from the tree building and online research for months, if not longer.

            That Saturday morning, Randy called to say he and his team had identified a suspect in one of the biggest unsolved serial rapist cases in Dallas history: David Thomas Hawkins. Not only that, but the suspect was still alive and lived in North Texas. My heart raced with excitement. This was the first time in Dallas County history a criminal case had been solved using IGG.[17] We got lucky on Hawkins: A direct family member had uploaded a genetic DNA profile to a public open-source database.

            That is not the norm. IGG investigative work requires great patience. For example, the very first case Randy and I collaborated on was a capital murder from 1983 that took us three years to solve using IGG. But the takeaway is that we solved it. If a case qualifies for IGG, it can be solved. Some cases you will have to grind out more than others.

            IGG really does not work without traditional genealogical research, which involves tracing both close and distant relatives, extensively researching public records, scouring social media, and looking into other sources to establish relationships and potential ancestral links to the suspect. Some cases will require hundreds of hours of research that can take years. Determination and patience are vital.

            Investigators will examine publicly available historical records. They will connect biological family members to verify and grow the family tree. By combining the information provided by the public genetic database with traditional genealogical research, law enforcement can unravel previously unknown branches of the family tree, validate existing relationships, and gain a more comprehensive understanding of suspect’s biological lineage. In Dallas, all sorts of folks are doing the genealogical research. It started with the FBI using tree builders under independent contract. Now the FBI has its own people in-house building trees. Some local law enforcement agencies and even prosecutor offices use their own people, and those results are mixed. I try to use only the FBI, as they are truly the world leaders.

            There are pitfalls. Investigators should not assume anything. IGG investigations often reveal that someone who was previously thought to be a biological child to a known parent is not at all blood-related to that parent. And then there is the previously unknown high rate of incest in the United States that has been discovered with genetic genealogy and the inception of IGG in criminal investigations.[18] IGG brings secrets into the light.

Initial tree

Once law enforcement has built a family tree to a satisfactory initial level, they can start trying to identify potential suspects based on characteristics such as age, height, race, and criminal records. They eliminate unlikely suspects and focus on those fitting the suspect profile.

            In cases with multiple suspects in the pool, criminal records can be helpful. In cases involving murder and sexual offenses, there’s a decent chance the suspect has a history of other crimes such as domestic violence, aggravated assault, and of course prior sexual crimes. For IGG suspects, the criminal records for serious felonies will almost always be arrests only, charges that were reduced for pleas, or convictions that occurred prior to laws requiring DNA samples for felony convictions. Remember, the suspect is not in CODIS. Investigators really need to look beyond convictions to identify the suspect or suspects who fit the profile. There is no concern that someone may be wrongfully arrested based on their past because law enforcement does not arrest anyone until there’s a direct STR DNA match to the suspect. The investigative lead must be followed up with traditional police work and the gold standard of forensic identification evidence, STR DNA.

“We’re gonna need a bigger tree”

In the realm of IGG work, there sometimes comes a point when the family tree constructed by investigators reaches an impasse and requires further expansion. The most effective method to grow the tree is by incorporating more familial SNP profiles through reference testing, which involves the consensual collection of a DNA sample from a third-party individual. Identifying candidates for reference testing occurs during the initial stages of tree construction. Reference tests introduce new branches to the family tree by revealing additional genetic relatives, which can also aid in pruning non-relevant branches and verifying existing connections.

            Law enforcement should never reference-test anyone who may possibly be the suspect or have a relationship close enough to the suspect(s) it could jeopardize the investigation. People talk, especially family. The last thing we want is a suspect to get wind of the investigation—that creates a public safety risk to victims and any family members the suspect may think are cooperating with law enforcement. When it comes to reference testing, proceed with caution!

            The DOJ’s Interim Policy requires informed consent from all third parties before collecting a reference sample. There is an exception to this requirement when the collection of such a sample would compromise the investigation, and law enforcement needs prosecutorial approval to use this exception.

            For reference testing, law enforcement should utilize consumer SNP profile DNA kits; AncestryDNA is one brand (available at ancestry.com). These kits ensure that the tested individuals retain ownership and control over their genetic data. Law enforcement can access these results only with the individual’s explicit permission, thereby protecting privacy rights and maintaining a safeguard between citizens and law enforcement.

Suspect(s) identified

In IGG cases, law enforcement often narrows down the suspect pool to a small group of blood-related individuals, typically siblings or first cousins. Investigators then meticulously examine each suspect until they obtain a direct STR DNA confirmation necessary for an arrest. The initial focus should be on the suspect most likely to have committed the crime based on available evidence. However, the most apparent suspect is not always the perpetrator.

            Multiple cases have required law enforcement to collect surreptitious DNA samples from various suspects before identifying the correct match to the crime scene evidence. This meticulous approach underscores the value of IGG, which minimizes the risk of misidentification, as DNA evidence is irrefutable. Although time-consuming and potentially costly, it is imperative to await STR DNA confirmation before making any arrests to guard against wrongful arrests.

            The DOJ Interim Policy is clear: “A suspect shall not be arrested based solely on a genetic association generated by a GG [genetic genealogy] service. If a suspect is identified after a genetic association has occurred, STR DNA typing must be performed, and the suspect’s STR DNA profile must be directly compared to the forensic profile previously uploaded to CODIS. This comparison is necessary to confirm that the forensic sample could have originated from the suspect.”[19]

            In most scenarios, law enforcement will obtain a suspect’s STR DNA profile using a surreptitious collection method; the most common of these is the “trash pull.” It is critical that law enforcement follow all local, state, and federal laws when doing a trash pull. The DOJ Interim Policy also requires prosecutor concurrence to plan and execute a trash pull for IGG; failure to follow the law at this point can jeopardize the STR DNA testing. Law enforcement will need probable cause (PC) to make an arrest, and IGG should never be used as PC for an arrest or search. It should be treated akin to an anonymous tip in legal terms—guiding investigations but not serving as the basis for PC. A quick refresher on anonymous tips from Davis v. State:[20] An anonymous tip can initiate a police investigation but typically does not establish the requisite suspicion for investigative detention or PC for arrest without additional reliable facts. Similarly, IGG “tips” must be corroborated, and the subsequent investigation must yield additional case facts to establish probable cause, including a direct STR DNA comparison.[21]

            Once law enforcement matches a direct STR DNA profile to the STR DNA profile of the suspect, they have the proper PC to make an arrest and execute a buccal confirmation search warrant. 

IGG at trial

At trial, nothing changes. The prosecutor should not present IGG investigative evidence at trial. The evidence the prosecution will use to identify the defendant will be the buccal swab STR DNA confirmation testing that was taken subject to a search warrant or consent at the time of the defendant’s arrest. Prosecutors should introduce testimony from the witness who gathered the evidence at the crime scene, including sexual assault exams and autopsies. The prosecutor will then put on the witness, most likely a law enforcement officer, who took the defendant’s buccal swab. Finally, the prosecutor will call the STR DNA analyst to admit the DNA report and testify to its findings. Nothing changes.

            It is important to note, that just because IGG evidence does not need to be admitted at trial, IGG evidence must be turned over in discovery. There may be situations where pre-trial hearings on IGG evidence and IGG discovery are warranted. Law enforcement must preserve all relevant communications, notes, tree building records, relevant matches, and SNP testing results and maintain regular communication with prosecutors about the IGG evidence.

The future

The future of IGG and DNA technology in general continues to have great potential for meaningful impact solving violent crimes. Ten years ago, we all thought that the future of forensic DNA was Rapid DNA. Rapid DNA refers to the technology and processes that allow for the quick analysis and profiling of DNA samples.  Rapid DNA used on evidence is currently not admissible in any jurisdiction for criminal trials in the United States. It was expected to revolutionize criminal investigations, but its implementation has been slow. On the other hand, IGG has experienced swift adoption in recent years, becoming a common tool in criminal cases nationwide. Might there be a day in the not-so-distant future where these two emerging DNA technologies intersect? One can hope.

            During a conversation with nationally recognized DNA expert Dr. Robert Benjamin,[22] I discussed the potential of a SNP testing database to replace the current CODIS STR system for identifying suspects in violent crimes. According to scientific evidence, SNP testing offers a higher chance of identifying suspects compared to STR testing. Additionally, unlike CODIS, which includes only convicted felons, a SNP database could encompass everyone. That’s right, as you read this article today, you are related to someone who has uploaded his or her genetic DNA profile to a public database. It might be a very distant, low-centimorgan relationship, but it is there. Dr. Benjamin believed that from a scientific standpoint, there is no reason why SNP testing couldn’t be implemented similarly to CODIS.

            I also spoke with the former custodian of the National DNA Database at the FBI about the future of SNP testing and IGG. He mentioned two significant issues hindering the transition from a STR CODIS system to a SNP database: First, there is currently no standardized set of SNPs for comparison. Second, it would require retyping more than 20 million offender profiles and more than a million forensic profiles. However, he acknowledged the potential for SNPs to become a viable option for forensic databases in the future.

            The future of IGG will also be a big player in the world of wrongful convictions and exonerations. This incredible new ability to better identify suspects in pending criminal cases translates perfectly to helping identify wrongful conviction cases and exonerating those who have been wrongfully convicted. This is forensic science technology that will benefit us all.

            Indeed, SNP testing and IGG have the potential to greatly benefit not only law enforcement but also defense attorneys and innocence projects across the country. The availability of scientific technology that can provide more accurate information is invaluable in determining the truth. It is important to use this technology responsibly and ethically. When used in this manner, there are no limits to the power and capability of IGG in achieving justice, which is ultimately the goal for which we all strive. The exploration of SNP testing and IGG opens up new possibilities for the legal system to ensure fairness and accuracy in criminal investigations and court proceedings.

Conclusion

In summary, law enforcement should follow the DOJ Interim Policy for Forensic Genetic Genealogy, ensuring a CODIS-eligible DNA profile is uploaded and exhausting all traditional investigative methods. Investigators must build the family tree, conduct reference testing as needed, and perform surreptitious sample collections until an STR DNA match to the crime scene evidence is confirmed. An arrest should be made only after obtaining an STR DNA match, with a search warrant ready for a buccal swab confirmation at the time of arrest. All IGG investigative work must be preserved for case filings, and prosecutors should follow standard procedures for presenting DNA evidence at trial, ensuring the integrity and reliability of the investigation and prosecution process. As one investigator proclaimed, IGG “is the most powerful tool that I’ve seen come along in the [decades] that I’ve been in law enforcement.”[23] The excitement surrounding IGG for law enforcement and prosecutors is palpable. This innovative method is set to revolutionize investigations by leveraging genetic information to uncover vital leads and identify suspects in ways never thought possible.  As long as it is being used responsibility and ethically, IGG empowers investigators to make connections that can bring justice to victims and closure to families.  Once you experience the incredible power and life changing justice, healing, and closure IGG brings to your community, you will become captivated by its power and effectiveness.


[1]  The author’s opinions do not reflect and are not endorsed by the Department of Justice (BJA), the Sexual Assault Kit Initiative (SAKI), or the Dallas County Criminal District Attorney.

[2]  Dowdeswell T., Forensic Genetic Genealogy Project Dataset, August 2023, v.3, Mendeley Data, 2023, available at https://data.mendeley .com/datasets/82969bsmw4/3/files/3fd011e4-9844-4504-8929-f0a42b2ef21d.

[3]  Guerrini, C.J., Bash Brooks, W., Robinson, J.O., Fullerton, S.M., Zoorob, E., and McGuire, A.L., “IGG in the trenches: Results of an in-depth interview study on the practice, politics, and future of investigative genetic genealogy.” Forensic Sci Int., March 2024, available at ncbi.nlm.nih.gov/pmc/articles/PMC10984250.

[4]  A comprehensive analysis of cases in the dataset through December 31, 2020, is presented in: Dowdeswell, T., “Forensic genetic genealogy: a profile of cases solved,” Forensic Sci. Int. Genet. 58 (2022) 102679. The dataset continues to be updated and currently includes cases through August 2023.

[5]  Dowdeswell, T., “Forensic Genetic Genealogy Coding Book & Annotated Bibliography,” June 2023 v.2.1, Mendeley Data, 2023, available at https://data .mendeley.com/datasets/82969bsmw4/3/files/33b456ad-9fe3-42be-9a86-9c3330278457.

[6]  United States Department of Justice’s Interim Policy Forensic Genetic Genealogical DNA Analysis and Searching (2019), www.justice.gov/olp/page/file/ 1204386/dl. And yes, the “interim” policy is the most current one, even though it’s five years old.

[7]   Id. at Endnote 20.

[8] www.fbi.gov/how-we-can-help-you/more-fbi-services-and-information/freedom-of-information-privacy-act/department-of-justice-fbi-privacy-impact-assessments/vicap

[9]  National Institute of Justice (NIJ).

[10]  Press, R., “DNA Mixtures: A Forensic Science Explainer,” National Institute of Standards and Technology, U.S. Department of Commerce, April 3, 2019, nist.gov.

[11]  Principles of Forensic DNA for Officers of the Court, National Institute of Justice, June 21, 2023.

[12] United States Department of Justice’s “Interim Policy Forensic Genetic Genealogical DNA Analysis and Searching,” (2019).

[13]  Here is one example of the chart: https://dnapainter.com/tools/sharedcmv4.

[14] www.unthsc.edu/school-of-biomedical-sciences/chi-becomes-nations-first-public-lab-to-earn-accreditation-to-perform-forensic-genetic-genealogy

[15]  https://verogen.com/products/forenseq-kintelligence-kit/.

[16]  www.gedmatch.com/join-the-genetic-witness-program.

[17]  Hawkins was later convicted on three counts of aggravated rape and one count of Aggravated Sexual Assault. He was sentenced to four terms of life in prison. Hawkins confessed to more than 30 violent home invasion rapes using a firearm.

[18]  Zhang, S., “DNA tests are uncovering the true prevalence of incest,” The Atlantic, March 18, 2024.

[19]  United States Department of Justice’s “Interim Policy Forensic Genetic Genealogical DNA Analysis and Searching” (2019).

[20]  989 S.W.2d 859 (Tex.App.—Austin 1999, pet. ref’d).

[21]  See Clemons v. State, 605 S.W.2d 567, 570 (Tex.Crim.App.1980); Mann v. State, 525 S.W.2d 174, 176 (Tex.Crim.App.1975); State v. Simmang, 945 S.W.2d 219, 223 (Tex. App.—San Antonio 1997, no pet). However, an anonymous tip or telephone call alone rarely will establish the requisite level of suspicion necessary to justify an investigative detention. See White, 496 U.S. at 329, 110 S.Ct. 2412;5 Reynolds v. State, 962 S.W.2d 307, 311 (Tex.App.—Amarillo 1998, pet. ref’d); Parish v. State, 939 S.W.2d 201, 203 (Tex.App.—Austin 1997, no pet.). Normally, there must be some further indicia of reliability—additional facts from which a police officer may reasonably conclude that the tip is reliable and a detention is justified, much less probable cause for an arrest. See White, 496 U.S. at 329, 110 S.Ct. 2412; Davis, 794 S.W.2d at 125.

[22]  Conversation between author and Dr. Robert Benjamin outside the courtroom before his testimony in State v. Talyle Meaderds jury trial on August 10, 2022, in Dallas.

[23]  De Groot, N.F., Van Beers, B.C., and Meynen, G., “Commercial DNA tests and police investigations: a broad bioethical perspective,” J. Med. Ethics 47 (2021) 788–795.