Marcia King’s mother kept the same telephone number for thirty-seven years.
She kept the same house in Arkansas. She didn’t move. She didn’t disconnect. Marcia had hitchhiked out of town in 1980 and stopped calling, and her mother — like every mother in this position has done since the invention of the telephone — left the line open in case her daughter ever picked up on the other end.
In April of 2018, the call finally came.
It wasn’t Marcia.
It was the Miami County Sheriff’s Office in Troy, Ohio, telling a woman who had waited almost four decades that the unidentified body found beside Greenlee Road on April 28, 1981 — the young woman the press had nicknamed Buckskin Girl for the fringed leather poncho she had been wearing — was her daughter. Twenty-one years old. Strangled and beaten. Buried under a headstone that simply said Jane Doe.
The case had not been solved. Her killer was, and remains, unknown. But her name had come back.
Marcia King’s identification was the first cold case ever solved by forensic genetic genealogy. A blood sample preserved in an unrefrigerated tube since 1981 was processed, uploaded to the public genealogy database GEDmatch, and matched within four hours of computer searching to a first cousin once removed. A team of volunteer genealogists at the newly founded DNA Doe Project built the tree out from there. Two weeks later, a mother in Arkansas got the call.
Three weeks after that, on April 24, 2018, a 72-year-old former police officer named Joseph James DeAngelo was arrested in his front yard in Citrus Heights, California. The Golden State Killer. Caught the same way: GEDmatch, family tree, candidate identified, confirmation DNA pulled from his trash. I remember standing with my cohorts from the Los Angeles Forensic Science Academy and talking about this case and the validity of using discarded DNA and familial DNA databases to find criminals. It was walking a fine legal line at the time.
This case began a change in the way cold case investigations worked in the U.S.
Eventually, it seeped its way into crime fiction. I tackled the topic a few years ago when writing What Darkness Does.
If you write the genre, you can no longer write around forensic genetic genealogy. And if you’re going to write it, you have to write it right.
Why This Matters for Crime Writers
Cold case fiction used to live in a forgiving place. The case had gone cold because the science of the era couldn’t read the evidence. Your investigator’s job was to be present-day-clever about a past-tense problem.
Forensic Investigative Genetic Genealogy (FIGG) moves the goalposts. Evidence that was useless for forty years is suddenly usable and trackable. Crimes from the 1970s, 80s, and 90s are now solvable in ways the original detectives couldn’t have imagined. Hundreds of cases have been resolved this way since 2018. The U.S. Department of Justice issued formal policy on its use in 2019. CRC Press is releasing the first comprehensive practitioner’s guide to FIGG this month.
That’s not a problem for fiction. It’s a gift. Forensic genetic genealogy gives you a mechanism that finally works the way readers want a cold case to work — the past speaking, after years of silence — without the cheap rescue of a deathbed confession or a buried diary in the attic.
It only works on the page if you understand what FIGG actually does, what it doesn’t do, and where the writer’s instinct toward speed and tidiness is going to trip you up.
What Forensic Genetic Genealogy Actually Is
Plain English: FIGG combines DNA recovered from a crime scene with consumer genetic genealogy databases — places like GEDmatch and FamilyTreeDNA — to find relatives of an unknown suspect or an unknown victim. A forensic genealogist uses those matches to build a family tree backward and outward until the tree narrows to one viable candidate.
That candidate is a lead. Not a defendant. Not a confirmed suspect. Just a lead.
For a suspect-identification match, investigators then need to collect what is called a surreptitious sample. This is typcially an abandoned or discarded source of DNA sample — for instance a coffee cup, a water bottle, a tissue from a public trash can. This is legal if the sample is taken from public domain. That sample is then tested and compared against the original DNA profile from the case at hand.
For a victim-identification case like Marcia King’s, a relative agrees to give a confirmation DNA sample, and the unknown person becomes a known person again.
Two distinctions matter for fiction.
FIGG is not CODIS. The Combined DNA Index System is the federal database of DNA profiles from convicted offenders, arrestees, and unsolved crime scenes. CODIS hits when your suspect is already in the system. Forensic genetic genealogy works when they aren’t. That distinction is the whole point of the technique. A writer who collapses the two will lose any reader who has paid attention to the last six years of true crime.
FIGG isn’t fast. The lab work to generate a sequenceable profile from old, often degraded evidence takes weeks to months. The genealogy work that follows takes even more time. Difficult cases take months. The famously hard ones take a year or longer. The science moves quickly. The genealogy is patient, careful, and slow.
Where Crime Writers Are Getting It Wrong
After watching the field for the last several years, here are the misnomers that show up most often regarding FIGG.
The instant match. A writer’s investigator submits DNA on Tuesday and gets a name on Wednesday. In the real world, even Marcia King’s case — which made a hit in only four hours of searching — had been preceded by weeks of lab work to extract usable DNA from a 1981 blood sample most labs had already given up on. We have to compress the timeline some, but compress the timeline that much and you lose the texture that makes cold case fiction interesting in the first place.
Skipping the confirmation step. A FIGG match is a candidate. It’s not legal proof. The story doesn’t move from genealogy hit to courtroom. It moves from genealogy hit to a separate, traditional confirmation DNA sample, almost always from something the suspect discarded in public domain. A writer who skips this step is writing a case that wouldn’t survive the first defense motion.
Using the wrong databases. Since the 2019 DOJ policy, U.S. law enforcement is restricted to genealogy databases where users have explicitly opted in to law enforcement matching. That means GEDmatch (with the right setting) and FamilyTreeDNA. It does not mean Ancestry. It does not mean 23andMe. Those companies have refused law enforcement access. A writer who has investigators pulling matches from Ancestry is writing a scene that gets the case thrown out.
Treating the genealogist as scenery. Forensic genetic genealogy is not done by detectives. It’s done by trained genealogists. Not sworn officers of the law. Many of them are civilians. Some of them are former hobbyists who turned professional after the Golden State Killer breakthrough. They are the people who actually build the tree. If your manuscript is about a cold case solved by FIGG and there is no genealogist in the story, you need to go back and add them.
Ignoring the ethical layer. Real investigators, real prosecutors, and real defense attorneys are arguing about FIGG every day. About consent. About whose DNA gets used. About what happens when one family member’s spit kit puts their cousin in prison. That tension belongs in your fiction. It’s exactly the kind of moral territory crime writers were made for.
How I Used FIGG In What Darkness Does
In What Darkness Does, a fourteen-year-old named Flora finds a bone in the woods.
Flora is sharp, stubborn, and exactly the kind of kid who doesn’t let go of a question once it’s in her teeth. The bone goes to a forensic anthropologist, Dr. Samantha Eckhardt, at the University of Michigan. Dr. Eckhardt invites Flora to a two-day workshop where she’ll learn how to use forensic genetic genealogy to try to give the bone a name.
I wrote the workshop scenes carefully. I gave Dr. Eckhardt a line I want every crime writer to internalize before they write a single FIGG scene of their own:
I want you to have realistic expectations. You may not leave here today with a candidate lead.
That’s the whole field guide in one sentence. Realistic expectations. Maybe not today.
One scene I love in that storyline isn’t the moment Flora gets a DNA hit. It’s the scene where her aunt, Emily Hartford, comes back to the lab after a break and finds Flora hunched over the keyboard, fingers moving fast, eyes locked on the screen, refusing to come up for air. Emily asks if she wants a snack. Flora doesn’t hear her. Emily asks again.
Without looking up, Flora answers: What if this were your child or sibling or best friend who had gone missing, never to be heard from again? Wouldn’t you want to know as soon as possible?
That’s the heartbeat of FIGG.
The drama isn’t the technology. The drama is the moral urgency the technology gives a fourteen-year-old at a keyboard, condensed into a single sentence by a kid who has only just learned what the work costs.
Flora’s storyline didn’t come from nowhere. It came from a real program at Ramapo College in New Jersey, the same one I credit in the back of the book — Ramapo runs an investigative genetic genealogy boot camp, and the youngest person ever to help resolve a case using IGG was a high school student who took part in it. The classrooms are real. The cases are real. The kids are real.
What I needed Flora to model — and what I want every crime writer to take with them — is that FIGG is not glamorous. It’s tedious, careful, full of stretches where the only thing happening on the page is a person staring at a screen.
The drama lives in the patience. But the reward is worth the wait. And to illustrate this I stretched Flora’s FIGG storyline into book 6, Walking On White, releasing October 20, 2026. Flora will get her answers!
The Field Guide: FIGG Best Writing Practices
Practical things to do when forensic genetic genealogy enters your story.
- Write the timeline honestly. Give the lab time. Give the family tree time. Let your investigator be frustrated by the wait. The slowness is the realism.
- Write the genealogist as a character. Let them have a personality, a method, a doubt. Let your reader watch them work.
- Show the confirmation DNA moment. The discarded coffee cup, the swab from a hospital, the cigarette in a parking lot. That’s the beat where the candidate becomes the suspect. Don’t skip it.
- Use the right databases by name. FamilyTreeDNA. Mention the opt-in setting. Get this right and the readers who care will trust you on everything else.
- Build the family tree onto the page. A scene where your detective sees a name three generations away from a killer and starts to feel the case shift — that’s a scene that didn’t exist in the genre until 2018. It’s yours to invent.
- Let the candidate be a real person before they’re proven guilty. FIGG often surfaces ordinary people — fathers, neighbors, retired church deacons — whose DNA matched because their nephew did a Christmas-gift spit kit. Sit with that for a paragraph. The moral weight of the technique lives in that pause.
- Don’t forget victim identification. Most crime fiction uses FIGG to catch killers. Marcia King’s case is a reminder that it also gives names back to the dead. A novel that works the missing person’s side of the technique has a clear field in front of it.
The Ethics Seam Writers Should Rip Into
When a great-aunt sends her DNA to a consumer genealogy site to find out where her ancestors came from, she is not consenting to a future case being made against her grandnephew. The chain of relationship is invisible, intimate, and one-way. She doesn’t know who she is implicating. She can’t know.
That’s the moral seam every crime writer working in this space should put pressure on. Not to take a side, necessarily — only to acknowledge that the technique that brings closure to one family creates exposure for another. A character who has thoughts about that is more interesting than one who doesn’t. A scene where a relative is told your DNA is the reason we found him is one of the rawest moments fiction can offer right now, and almost no one has written it well yet.
That could be you.
Why This Tool Earns Its Place in the Genre
The cases forensic genetic genealogy has solved are the cases that broke families for decades. Children waited their whole adult lives to learn who killed their mothers. Parents died not knowing what had happened to their daughters. The technique can’t undo any of that. It doesn’t give back the years.
What it does is end the unknowing. And the unknowing, as I have written before, is the part of grief no one survives well.
In April of 2018, a mother in Arkansas finally got an answer about a daughter she had never stopped waiting for. The headstone in Riverside Cemetery in Troy, Ohio, that had said Jane Doe for thirty-seven years got a name carved into it: Marcia Lenore Sossoman King. The murder is still open. The killer hasn’t been caught. But Marcia is no longer Buckskin Girl. She is herself again, in death, the way she was in life.
Every crime writer who writes in cold case territory is, in some sense, writing toward that exact moment — the unknowing that finally breaks. FIGG deserves a place in crime fiction. It deserves to be written without shortcuts. It deserves to be written by people who understand that the truth at the end of the family tree belongs first to the family of the victim.
Get the science and technique right. Get the genealogy right. Get the long process right.
The story takes care of itself from there.
Want more on writing forensics that actually holds up? My Crime Writer’s Toolkit and the Master Crime Writing Course at forensicspeak.com walk through the procedures, evidence types, and craft principles that separate the novels readers trust from the ones they put down on page forty.
Jennifer Dornbush is an author, screenwriter, and forensic specialist who brings crime stories to life with authenticity and heart. With a background rooted in real-world forensics and a passion for crafting unforgettable mysteries, Jennifer offers readers and viewers a front-row seat to the intersection of science, justice, and human nature. Jennifer’s crime expertise has made her a sought-after speaker, consultant, and educator. Through her webinars and master courses, Jennifer guides writers in melding suspenseful storytelling with forensic realism to the screen and page. Meet her at www.jenniferdornbush.com
Sources
- DNA Doe Project. Buckskin Girl Case File: Marcia King. https://dnadoeproject.org/case/buckskin-girl/
- Lima News / AIM Media Midwest. “‘Buckskin Girl’ identified.” April 16, 2018.
- S. Department of Justice, Office of the Deputy Attorney General. Interim Policy on Forensic Genetic Genealogical DNA Analysis and Searching. September 2019. https://www.justice.gov/olp/page/file/1204386/dl
- Federal Bureau of Investigation. Cold Case Investigations. https://www.fbi.gov/investigate/violent-crime/cold-cases
- Vacca, John R., editor. Forensic Investigative Genetic Genealogy (FIGG) and DNA Evidence: A Guide for Practitioners. CRC Press, 2026.
- Ramapo College of New Jersey, Investigative Genetic Genealogy Center. https://www.ramapo.edu/igg
