- Today with a swab of your cheek, do it yourself DNA kits promise to unlock everything from your future health risk to a map of your ancestry.

But the biggest breakthrough may well be for law enforcement, a growing number of cold cases are being solved using DNA data that private citizens have submitted to genealogy websites.

And that's opening up a whole new range of concerns about the power of DNA and the perils to our privacy.

- This story really begins in the 1980's.

Not in a high tech DNA lab but when police in a sleepy New Hampshire town found a mysterious barrel in the woods.

Little did they know that it would put them in the middle of today's DNA controversy.

(humming) (typing) - We've called this press briefing today because we have additional information regarding the Allenstown New Hampshire murder case.

- [CeCe Moore] This case, I don't know what to call it but what's really a one in a million chance.

I don't know if it was meant to be or if it's just a happenstance.

But it was certainly not something that was foreseen by anyone.

- [Spokesperson] Based on DNA testing and genealogical research, we've identified three of the Allenstown murder victims.

- [CeCe] And now with the use of genetic genealogy for law enforcement purposes, I think we've seen the next big breakthrough.

- [Interviewer] Genetic genealogy.

- Genetic genealogy.

- Genetic genealogy.

- Thanks to the rise in personal genetic testing kits a big break has lead to an arrest in an infamous cold case.

- [News Anchors] Law enforcement agencies used the technique in at least eleven, fifteen, forty three cases nation wide.

- This is the most significant happening in criminal investigations in decades.

- [Male Host] The promise is real and the technology cutting edge but today's use of DNA science and genealogy research to solve crimes arose out of a tangled cross country police investigation sparked by a curious telephone call made nearly twenty years ago.

- [Gruenheid] In September 2002, a friend contacted our Sheriff's dispatch to report that her friend Eunsoon had been missing.

The deputy went out to the residents and contacted Eunsoon Jun's common law husband.

A gentlemen by the name of Lawrence William Vanner.

- [Male Host] Vanner acted suspiciously and police brought him in for questioning.

- Your not my priest - [Detective] No.

- And your not my doctor but I'm just not gunna say anything more about Eunsoon or myself right now.

(clock ticking loudly) - [Detective] Maybe she's hurt herself and you're concerned about that getting out that she's harmed herself.

- No.

- [Male Host] Vanner was a compleat enigma.

- [Gruenheid] There was no drivers license, there was no criminal history and that's really unusual.

That's like a ghost person.

- [Male Host] On the ride to the records bureau for fingerprinting Detective Gruenheid struck up a conversation in the backseat.

- [Gruenheid] Whenever your interviewing somebody you always wanna try to find some sorta common thread, and I said somthing that you know, where'd you grow up.

And all of sudden he stopped and he looked at me, he had these bright piercing blue eyes.

And he kinda like leaned in a little bit and he said "that's none of your damn business."

(door opening) - Alright Larry, your prints came back.

You know your other name, right?

- [Man] Curtis or Gerald or Gerry or whatever name you're going by this week.

- Curtis Kimball.

- [Man] Curtis Kimball - [Male Host] Curtis Kimball that's how his fingerprints identified him, he jumped parole and had been on the run for twelve years.

Gruenheid went back to search Jun's house.

- [Gruenheid] My partner and I went around to the garage.

My partner took a few steps in and he told me you need to come in here and take a look at this.

- [Male Host] Inside was an enormous mound of cat litter.

Scrapping some of it aside, revealed a human foot, with a flip flop still on it.

Eunsoon Jun was no longer missing.

(slow bells ringing) Vanner, charged with Juns murder was soon connected to another alias.

Gordon Jensen, Jensen had abandoned a five year old girl named Lisa, believed to be his daughter sixteen years earlier at a Northern California RV park.

Gruenheid tracked down Lisa, now an adult and a DNA test revealed that Lisa wasn't his daughter after all.

- [Gruenheid] I'm reading all through this and my mind is going, where did he get this girl?

- [Jason Moon] Investigators do not know her identity, and so Lisa becomes a sorta living Jane Doe.

- [Male Host] And because of all his aliases police had no idea who the man really was.

- It became a quest of mine to try to identify her and identify him.

(eerie music) - [Moon] It was 1985 and there were a group of kids who lived in the Bear Brook Gardens trailer park.

And they were basically playing hide and seek.

And they found a barrel and didn't realize what they had actually found until later that fall when a hunter came across the same barrel.

- Was on routine patrol I was dispatched to the area of Bear Brook Gardens number one and that's when I found a body that was decomposed and it was dismembered.

- [Moon] There are remains of two people.

One an adult female the other is a female child.

- [Male Host] But the case went cold until 2000.

When a State Trooper stumbled upon a second barrel just one hundred yards away from the first one.

- [Moon] In the second barrel were the remains of two more victims, these were both young girls.

They had been out there just as long as the victims in the fist barrel.

- In 1985 DNA wasn't scientifically accepted in law enforcement, we didn't even have computers.

My report was done on an IBM electric typewriter with carbon paper.

- [Male Host] Crime scene DNA technology burst into use shortly after the first barrel was found.

- [News anchor] Today police can get what they call a DNA fingerprint.

- [Male Host] But in this case the bodies had deteriorated so badly the samples were useless for DNA forensics of the time.

- When you don't have the identity of the victims its almost impossible to learn anything about who might have killed them.

- [Woman] Your DNA plays a big part in defining who you are.

- [Male Host] But by 2015 DNA testing had become mainstream.

- [Woman] It can even unlock family mysteries from your distant past.

- [Male Host] And Lisa, the girl who had been abandoned at the California Trailer park years earlier still didn't know who she was, but she had an idea.

Was there a way to use the genealogy test that had become so popular to find her own family.

So police reached out to Barbara Rea-Venter an expert in helping adoptees find their birth parents.

- I've never worked on a Jane Doe case like this before.

She's the ultimate test of how this technic works because we quite literally knew nothing about her.

- [Male Host] Lisa submitted her DNA and Rae-Venter and her team began constructing her family tree.

- [Rae-Venter] She had two fairly close matches.

One was on Ancestry and then she had another match on 23andMe.

We know from matching DNA that one of Lisa's parents has to be a first cousin once removed to the matches.

- [Male Host] The team then used public records to build out the family trees of those matches.

While police asked the newly ID'd relatives if they would submit to a DNA test to see if they were even more closely related to Lisa.

The case would become a prove of concept for law enforcement - [Moon] It took upwards of ten thousand hours to do this but eventually they did narrow down Lisa's family tree to a family in New Hampshire.

- [Male Host] In July of 2016 Rae-Venter and police felt they finally could tell Lisa who she was.

Her name was Dawn Beaudin and as an infant she and her mother Denise had gone missing from Manchester New Hampshire.

- [Moon] One Thanksgiving Denise's family comes over to visit and she's gone.

The house is empty and that was the last that they had seen of her and at the time she had a boyfriend who was going by the name of Bob Evans.

- So who the heck is Bob Evans?

- [Male Host] To answer that question New Hampshire authorities, turn to a photo sent to them by police in California.

- [Rae-Venter] They sent a picture of the guy who had been Lisa's abductor who had a whole string of aliases, and used the name Lary Vanner.

- [Mark Gelinas] The state police came to my house.

They took a picture and threw it on the table and said you know who that is?

And I said yeah its Bob Evans.

- [Male Host] Mark Gelinas knew this man, they worked at the same New Hampshire mill in the 80's.

After thirty years authorities announced they knew who the Bear Brook murderer was.

After DNA test revealed that his biological daughter had been inside one of the barrels.

- In New Hampshire he was known as Bob Evans.

- [Moon] He's a serial killer, Eunsoon Jun, Bear Brook victims.

Lisa's kidnapping, he was the same guy and what happened to Denise, we don't know.

- [Male Host] Bob Evans never answered for his Bear Brook victims, he died in prison in 2010.

After pleading guilty to the murder of Eunsoon Jun.

- [Moon] But the investigation into the identity of Lisa kicks of this you know this revolution to how we use DNA to solve crimes.

- [Male Host] After Bear Brook, detectives in California wondered if the same DNA techniques could be used to help solve one of America's biggest mystery's.

- [Voice] I wanna kill you.

- The Golden State killer.

- The Golden State killer.

- [TV Host] Violent and ruthless rampage started in the 1970's.

- [Rae-Venter] I was pretty confident that we could solve it, it's exactly the same technique.

- [Male Host] Commercial genealogy websites like Ancestry.com and 23andme say its their policy not to allow law enforcement to search their databases.

So Rae-Venter used GEDmatch, an open source database where people voluntarily upload their DNA profiles.

Sixty three days later she had a match.

- [Unknown Man] Tonight a four decade old search for one of history's most infamous serial killers may be over.

The elusive Golden State.

- The Golden State killer changed everything.

- [Male Host] After that arrest in 2018, genetic genealogist CeCe Moore began working with law enforcement, after GEDmatch clarified its policy.

- [Moore] That meant people now knew and had the choice to have their DNA used in this way or not.

I had received dozens and dozens of inquires asking if I could use my techniques.

- [Male Host] In the past year alone Moore and her team at Parabon NanoLabs have used genetic genealogy to unearth new information about more than fifty cold cases.

- [Sheriff] The suspects DNA collected at the scene was used to identify his ancestors which in turn led us the identification of Talbit.

- [Male Host] With the detectives narrowing in on people based on the DNA of their genetic relatives.

Privacy concerns are growing.

- Everyone wants to catch the bad guy.

My question is though at what cost?

(loud bell ringing) - [representative] Delegate Sydonor with house bill 30.

- [Sydonor] My DNA is my DNA and my DNA will be my children's DNA and their children and their children's children.

So when you allow governments to begin using these techniques your essentially creating a huge genealogical dragnet that even if I consented my children, their children and their children's children they never consented to.

- [Male Host] In May 2019 GEDmatch changed its policy.

So users have to opt in to allow for aw enforcement searches.

- [Moon] Most people would agree that solving cold cases and identifying remains are worthy and noble causes but you start talking about a big database full of everyone's DNA.

You know I think people start to get a little nervous.

- [Male Host] Today an estimated twenty nine million people have added their DNA to the leading databases.

And while those are private, people still continue to upload their profiles to publicly available databases.

- Essentially we chasin after a genie that's already been let out of the bottle and trying to figure out how to contain it, how to regulate it.

- [Male Host] In the Bear Brook case Rae-Venter used genetic genealogy to discover one final detail about the murderer.

- In New Hampshire he called himself Bob Evans.

That mans real name was Terry Rasmussen.

- [Male Host] And after an amateur genealogist heard Jason Moon report Rasmussen's identity in his Pod cast she helped police identify the other three Bear Brook victims.

(walking) But Lisa's mother Denise Beaudin remains missing and no one knows how many other victims Rasmussen may have claimed.

- Now I've always tried to live by the motto that there's no defense against the truth.

But sometimes it's hard to find out what the truth is.

- [Moon] Genetic genealogy raises really interesting questions about who owns genetic information.

Its really hard to find analogies to it in other areas of science and the law because your DNA simultaneously the most person thing about you but its also shared amongst all of us.