Will French Investigators Soon Use American DNA Databases to Solve Cold Cases?
France is now debating landmark legislation that could allow investigators to tap into U.S. consumer genealogy platforms like GEDmatch — a move that would dramatically expand cold-case forensics, but also raise thorny questions about bioethics and privacy.
For decades, France has maintained some of the strictest laws in Europe around genetic testing — banning even recreational ancestry DNA kits. Now, in a striking policy reversal, French legislators are actively debating whether their investigators should be permitted to reach across the Atlantic and tap into sprawling American DNA genealogy databases to crack cold cases that have stumped investigators for years.
The Proposal: What Is France Considering?
According to a February 2026 report from Le Monde, French investigators and legislators are seriously exploring the possibility of allowing law enforcement to use U.S.-based consumer genealogy databases — platforms like GEDmatch, FamilyTreeDNA, and potentially others — as investigative tools in cold case criminology. The discussion is active at the parliamentary level, marking a significant shift in France's historically conservative approach to genetic data.
Currently, France's domestic DNA infrastructure revolves around the FNAEG (Fichier National Automatisé des Empreintes Génétiques) — the National Automated Genetic Fingerprint File. As of late 2024, the FNAEG holds approximately 4.4 million DNA profiles, making it the second-largest forensic DNA database in Europe. But the FNAEG is a traditional criminal database: it stores STR (Short Tandem Repeat) profiles from convicted criminals and suspects, and its ability to do "familial searching" is limited to close relatives like parents, siblings, or offspring.
The key limitation? If a perpetrator has never been arrested or convicted, their DNA isn't in FNAEG at all. That's precisely the gap that investigative genetic genealogy — using consumer DNA databases — is designed to fill.
France's Bioethics Law currently restricts DNA testing to medical, judicial, or specific scientific purposes. This means recreational genealogy testing by private companies is effectively banned domestically, and France is widely considered the last country in Europe where consumer ancestry DNA testing remains illegal. The proposed reform would need to carefully carve out a forensic exception while navigating GDPR and the French Commission Nationale de l'Informatique et des Libertés (CNIL).
What Is Investigative Genetic Genealogy (IGG)?
For those new to the field, Investigative Genetic Genealogy (IGG) — also called Forensic Genetic Genealogy — is a powerful technique that combines traditional DNA profiling with genealogical research to identify unknown suspects or victims in criminal cases. Here's how it works:
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01DNA Recovery from Crime Scene Investigators collect biological evidence — blood, hair, saliva, or even "touch DNA" — from the scene. Even trace amounts are sufficient with modern Next Generation Sequencing (NGS) methods.
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02SNP Profile Generation Unlike traditional STR profiling used in CODIS or FNAEG, IGG generates a Single Nucleotide Polymorphism (SNP) profile — analysing between 500,000 to 1 million data points across the entire genome. This is the same type of profile generated by consumer ancestry kits.
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03Upload to Genealogy Database The SNP profile is uploaded to an open-access platform like GEDmatch, which holds approximately 1.5 million voluntarily submitted profiles from people worldwide who have used ancestry testing services. Algorithms scan for partial matches indicating shared ancestry.
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04Family Tree Reconstruction Specialist genealogists — not just the DNA software — painstakingly build out family trees from the partial matches. A second or third cousin match can be the starting point for tracing back to a common ancestor and then forward again to identify the likely suspect pool.
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05Suspect Confirmation Once a likely suspect is identified, investigators obtain a direct DNA sample — usually from a discarded item, with a warrant — and compare it to the original crime scene profile to confirm a match. This is the definitive legal evidence step.
Data from GEDmatch suggests that with approximately 1.2–1.5 million profiles in its database, it can identify a third cousin or closer for over 90% of individuals of predominantly European descent. This makes the database extraordinarily powerful for identifying suspects from populations with significant representation in it — which includes a large segment of French-heritage individuals, given historical emigration patterns to the United States.
The Case That Changed Everything: The Golden State Killer
Joseph James DeAngelo — The Golden State Killer
For over 40 years, a serial killer, rapist, and burglar terrorized California — committing at least 13 murders, 50 sexual assaults, and over 100 burglaries between 1976 and 1986. Traditional investigations, including searching CODIS, the U.S. equivalent of France's FNAEG, yielded nothing.
In 2018, investigators uploaded crime scene DNA to GEDmatch and identified distant relatives of the unknown perpetrator. Expert genealogist CeCe Moore and her team reconstructed family trees until they converged on former police officer Joseph James DeAngelo. His DNA from a discarded item confirmed the match. He was arrested in April 2018 and pleaded guilty to 13 counts of first-degree murder in 2020, receiving life imprisonment without parole.
The case didn't just close a chapter — it launched a revolution in forensic science and caused law enforcement agencies worldwide, including French forensic scientists at the IRCGN (Institut de Recherche Criminelle de la Gendarmerie Nationale), to take serious notice.
The Golden State Killer arrest was followed by numerous other high-profile resolutions: the Gilgo Beach murders (Rex Heuermann arrested 2023), the Grim Sleeper case in Los Angeles, and many hundreds of less-publicised homicide and sexual assault cold cases across North America. By early 2026, IGG has helped bring closure to over 1,000 cases in the United States and Canada alone.
Recent uses of recreational databases to identify individuals in criminal cases in the United States open up a new exploration path for the use of NGS applied to forensic genealogy. However, national regulations must adapt to these new opportunities.
— Institut de Recherche Criminelle de la Gendarmerie Nationale (IRCGN), French Gendarmerie Forensic Science InstituteFrance's Unique Legal Barriers — And Why This Matters
France's regulatory position on DNA has historically been among the most restrictive in Europe. Under the current French Bioethics Law, genetic testing is only authorised for medical, scientific, or specific judicial purposes. This has created an unusual paradox: France has the second-largest forensic DNA database in Europe, yet its investigators cannot legally use the same genealogy platforms that have cracked hundreds of American cold cases.
The FNAEG's structural limitations are well-documented. It uses STR profiling — effective for exact matches and very close relatives — but lacks the SNP-based architecture needed for distant familial matching. France's French Gendarmerie forensic scientists have explicitly acknowledged that U.S.-style genealogy database access represents a compelling new investigative path, pending legal adaptation.
Any reform would need to navigate multiple regulatory layers:
Accessing databases held by U.S. companies creates cross-border data transfer issues under EU data protection regulations.
France's data protection authority (CNIL) would need to issue specific guidance on lawful basis for such forensic searches.
The existing Bioethics Law would likely require a parliamentary amendment to create an explicit forensic genealogy exception.
Only GEDmatch PRO and FamilyTreeDNA explicitly allow law enforcement access — Ancestry and 23andMe do not.
Critically, it is worth noting that only a limited number of genealogy platforms currently cooperate with law enforcement investigations. GEDmatch (now owned by Verogen/QIAGEN, a forensic DNA company) and FamilyTreeDNA explicitly permit law enforcement access, while the two largest platforms — AncestryDNA (approx. 23 million profiles) and 23andMe (approx. 14 million profiles) — explicitly prohibit such access and have stated they would legally challenge any court-ordered warrant compelling access.
The Bioethical Battleground: Arguments For and Against
The French proposal sits at the intersection of one of the most contested frontiers in modern forensic science. Globally, bioethicists, privacy advocates, forensic scientists, and law enforcement are deeply divided. Here is where the key arguments fall:
| ✅ Arguments in Favour | ⚠️ Arguments Against / Concerns |
|---|---|
| Solves otherwise-unsolvable cold cases where the perpetrator has no prior criminal record | Users submitted DNA for ancestry research, not criminal investigations — raising serious informed consent concerns |
| Provides justice for victims' families who have waited decades | Innocent relatives of a suspect can be incorrectly targeted before the right person is identified |
| Works as a "last resort" tool when all other methods have failed | Databases are predominantly of European/white descent — creating racial imbalance in who can be identified |
| Proven track record: 651+ solved cases globally as of late 2023 | Potential for "genetic dragnetting" — placing entire family networks under suspicion without cause |
| French people of European heritage are heavily represented in American genealogy databases through emigrant relatives | Cross-jurisdictional data transfers create GDPR complications and sovereignty questions |
| Technology is improving rapidly; older damaged crime scene DNA can now yield results | Documented cases of loopholes being exploited — investigators bypassing opt-out settings on GEDmatch |
The risks are not hypothetical. In a well-documented case, Michael Usry was wrongly identified as a suspect in the 1996 murder of Angie Dodge in Idaho Falls, USA. Police obtained a court order compelling Ancestry to disclose the identity behind a partial GEDmatch match, which led to Usry — who was ultimately cleared after a direct DNA test proved he was not a full match. The experience was deeply traumatic for an innocent man whose only "connection" to the crime was a distant shared ancestor. This case remains a key reference point in the global debate about IGG regulation.
How Is the Rest of Europe Approaching This?
France would not be the first European country to grapple with investigative genetic genealogy. The technique has already been applied in several European jurisdictions, though always in legal grey zones or under highly specific court-approved frameworks:
The Netherlands
Dutch investigators made some of the earliest European uses of IGG, with forensic scientists involved in landmark cases that demonstrated the technique's potential even with degraded or partial crime scene DNA. However, the legal framework remains incomplete.
United Kingdom
The UK holds over 7 million profiles in its National DNA Database (NDNAD) and has operated familial searching of close relatives since 2002 — but current UK guidance explicitly prohibits police from using IGG for unknown suspect identification, citing unresolved concerns about privacy, consent, and proportionality. England and Wales solved the 1984 cold case murder of Melanie Road using traditional familial searching — but not IGG.
Belgium and Germany
Both countries have undertaken academic and parliamentary discussions about IGG but have not enacted any permissive legislation. Germany's strict historical sensitivities around genetic data make reform particularly challenging politically.
At the European legal level, a January 2025 paper in ScienceDirect specifically analysed how EU member states can legally deploy investigative genetic genealogy, warning against relying on the "manifestly made public" legal basis under GDPR as justification for accessing genealogy databases — a significant legal nuance for any French reform proposal.
As a forensic science student, this story is one to watch very closely. If France passes this legislation, it will set a transformative precedent for all of Europe and potentially reshape how cold cases are approached across the EU. It will also define critical boundaries around what forensic scientists, criminologists, and legal professionals must consider when deploying cutting-edge DNA technology — balancing justice with the protection of genetic privacy as a fundamental human right.
Key Developments to Follow
The French legislative debate is active, but several crucial questions remain unresolved — and will determine whether this proposal becomes law or stalls under ethical opposition:
- Parliamentary Timeline: Will a formal bill be tabled in the Assemblée Nationale, and when will committee hearings begin?
- CNIL Position: France's data protection authority has not yet publicly responded to the proposal. Its stance will be critical.
- GDPR Compatibility: Legal scholars must determine whether accessing U.S.-hosted databases from a French law enforcement context is permissible under EU data law.
- Database Cooperation: Would GEDmatch or FamilyTreeDNA enter formal agreements with French investigators? What protocols would govern access?
- Scope Limitations: Would the law restrict IGG to only the most serious cases — murder, sexual assault — as recommended by U.S. Department of Justice guidelines?
The U.S. experience provides a cautionary tale about the patchwork of regulation that emerges without a clear national standard. By early 2026, approximately nine American states require warrants or court orders for police to use consumer DNA databases — while others remain unregulated. France has the opportunity to learn from this and design a clear, proportionate, ethically grounded framework from the outset.
