DNA Phenotyping Unmasks Golden State Killer
DNA Phenotyping has the ability to heat up cold cases and catch serial killers. Which happened this week in the Golden State Killer case. The cutting-edge forensic technique led investigators to Joseph James DeAngelo. DNA linked him to 175 crimes, including burglary, serial rape, and serial murder.
What is DNA Phenotyping?
It’s the prediction of physical appearance from DNA. It can be used to generate leads in cases where there are no suspects or database hits, to identify human remains, and to narrow suspect lists.
DNA carries the genetic instruction set for an individual’s physical characteristics. By determining how genetic information translates into physical appearance, it’s possible to reverse-engineer DNA into a physical profile. Parabon Snapshot reads tens of thousands of genetic variants — aka “genotypes” — from a DNA sample and uses this information to predict what an unknown person looks like, including genetic ancestry, eye color, hair color, skin tone, freckling, and face shape from any ethnic background, even with people from mixed ancestry.
Some traits are partially determined by environmental factors, rather than DNA alone. Parabon Snapshot trait predictions reflect the degree to which such factors influence each particular trait. Traits that are highly heritable, such as eye color, have a higher accuracy and confidence than those with lower heritability.
It’s this very technique which narrowed in on a suspect in the Golden State Killer case. Using DNA collected in 1987, authorities created images of the suspect: Caucasian, green or hazel eyes, with blond hair. Snapshot showed images of him at ages 25, 45, and 65. The information stated the man may also have freckles and be thinner or heavier than the images indicated.
Check out the Snapshot image (left) vs. Joseph James DeAngelo (right).
For six days, detectives followed Joseph James DeAngelo, a former police officer, waiting for him to throw away an item that contained his DNA. Through the DNA, law enforcement linked DeAngelo to 175 crimes between 1976 – 1986. On Wednesday around 2:30 a.m., Joseph James DeAngelo was taken into custody without incident. Later that day, the DA’s office filed the first charges in the case, two counts of murder — the Feb. 2, 1978 slayings of Katie and Brian Maggiore in Rancho Cordova.
Looking for inspiration? How about digging into an unsolved murder case? DNA Phenotyping has spat out numerous faces, even images of LEOs who offered up their genetic material to prove DNA Phenotyping works.
Who Is the Golden State Killer?
Joseph James DeAngelo was born in Bath, N.Y., but graduated from Folsom High School in suburban Sacramento in June 1964, according to USA Today. He enlisted in the Navy during the Vietnam War, returned home as a decorated vet, and earned an associate’s degree in police science from Sierra College and a bachelor’s degree in criminal justice at Sacramento State, the The Sacramento Bee reported. In the fall of 1973, he wed Sharon Marie Huddle of Citrus Heights at Auburn First Congregational Church. The two later divorced. He lived with a daughter and granddaughter until his arrest.
Work Background & Crimes
DeAngelo lived in the same area of other crimes. While working as a police officer in Exeter, California from 1973 to 1976, the Visalia Ransacker burglarized more than 85 homes and killed a journalism professor. Many believed the Visalia Ransacker and the East Area Rapist were one in the same. Visalia is located ten miles from Exeter, so it’s probably a safe assumption.
DeAngelo also worked in Auburn, where he was a police officer. In 1976, some believe it’s here where he committed his first rape. By 1979 the Auburn Police Department no longer employed DeAngelo. He chose to turn in his resignation rather than face shoplifting charges. Only now after his arrest can we understand why he didn’t want to pursue an administrative hearing or let investigators pry into his personal affairs.
The items he stole piqued my interest: a hammer and a can of dog repellent. Did he not want to leave a paper trail so he could use these items on his victims?
“He had one main feature that he would do on his crimes,” said Sgt. Paul Belli, with the Sacramento County Sheriff’s Department. “He would get into homes through an unlocked door or a cracked window and use shoelaces to tie up victims. He would enter homes through an unlocked door or cracked window, and seemed to target homes where a couple was present.”
When the Sacramento area rapes were first reported, women either lived alone or were home with their children. By 1977, a year after his first known attack, he expanded to couples. He’d bind the boyfriend/husband’s wrists and ankles, then balance dishes on his lap or belly (if prone) so he could hear if the distraught man moved while he raped his girlfriend/wife in the next room. His first known homicides occurred when the East Area Rapist killed Brian and Katie Maggiore after the couple — out walking their dog at the time — may have spotted him breaking into a home in Rancho Cordova, California, in February 1978.
“These cases are some of the most horrific I’ve had to investigate,” said Erika Hutchcraft, an investigator for Orange County District Attorney’s Office. “They’re not a one-time, you know, crime of passion, but these are almost passionless crimes. Very cold, very violent.”
As he committed crimes across the state, authorities called him by different names. When he started raping in Northern California, the media dubbed him the East Area Rapist. After a series of slayings in Southern California, he became known as the Original Night Stalker. In two murder cases that involved an elaborate binding method, authorities hunted for the Diamond Knot Killer. True crime writer Michelle McNamara named him the Golden State Killer. 
As reported by 48 Hours, “Michelle wrote an article about EARONS in 2013. She had details from bits of information she gleaned online and more explicit details from investigators on the case. The odd acronym EARONS (short for East Area Rapist/Original Night Stalker) was not a name many knew. So Michelle decided to rebrand him, hoping to give him a higher profile. Working with her editor at Los Angeles Magazine, they said, ‘You know what, this Golden State Killer, it shows just the breadth of him having hit Northern California, Southern California, and then sort of right in the middle.’ With that, EARONS became the Golden State Killer.”
The Golden State Killer’s timeline can be found HERE. A slideshow of the evidence prior to the arrest can be found HERE.
“Over the years, we heard of homicides down in Southern California, and we thought it was the East Area Rapist,” said Larry Crompton, a retired detective for Contra Costa County Sheriff’s Department. “But he would not leave fingerprints, so we could not prove, other than his M.O., that he was the same person. We did not know anything about DNA.”
The arrest brought international attention.
A recent New York Times bestseller by true crime writer Michelle McNamara — who died suddenly in 2016 — tells the story of the East Area Rapist/Original Night Stalker turned Golden State Killer. Michelle McNamara dedicated ten years of her life to this case, and then died before being able to write the ending. Her husband, comedian/actor Patton Oswalt, along with the help of her research partner, finished the book for her. I’ll Be Gone in the Dark: One Woman’s Obsessive Search for the Golden State Killer was published in February of this year.
I haven’t read the book, but from what I understand McNamara homed in on DeAngelo. Which is pretty amazing, considering she had no law enforcement background.
“She had a mind for the details of true crime the way that other people have for baseball or me for films,” said Oswalt. “She could recall the details of pretty much every late 20th and 21st century crime. It was just in her head.”
I can’t help but wonder if Michelle McNamara helped orchestrate the arrest from heaven. It seems too coincidental that DeAngelo was arrested on National DNA Day.
In the Sacramento County Jail is where DeAngelo sits while he awaits his first court appearance on Friday afternoon. Thanks to DNA Phenotyping and some fine police work California residents can rest easy tonight, knowing the East Area Rapist/Original Night Stalker/Diamond Knot Killer/Ransacker/Golden State Killer will finally pay for his crimes.
UPDATE: DNA Phenotyping was one investigative tool used by Aurora PD. After this post was written and more information came to light, the DA admitted to using familial DNA searches to narrow in on DeAngelo. It’s a risky move since some view familial DNA as unconstitutional. Watch this space for more updates as they become available.
UPDATE: Author James L’Etoile wrote a fantastic article about GEDMatch, an open source DNA registry used by law enforcement in the DeAngelo case. Find out why LEOs can legally use the registry to create a family tree by reading his post.
Exciting news! SCATHED, Grafton County Series, Book 3, will release in August, 2018. Haven’t caught up with the series? Look inside MARRED and CLEAVED on Amazon, or read an excerpt HERE and HERE.
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Sue Coletta
Sue Coletta is an award-winning crime writer and an active member of Mystery Writers of America, Sisters in Crime, and International Thriller Writers. Feedspot and Expertido.org named her Murder Blog as “Best 100 Crime Blogs on the Net.” She also blogs on the Kill Zone (Writer's Digest "101 Best Websites for Writers"), Writers Helping Writers, and StoryEmpire. Sue lives with her husband in the Lakes Region of New Hampshire. Her backlist includes psychological thrillers, the Mayhem Series (books 1-3) and Grafton County Series, and true crime/narrative nonfiction. Now, she exclusively writes eco-thrillers, Mayhem Series (books 4-9 and continuing). Sue's appeared on the Emmy award-winning true crime series, Storm of Suspicion, and three episodes of A Time to Kill on Investigation Discovery. When she's not writing, she loves spending time with her murder of crows, who live free but come when called by name. And nature feeds her soul.
29 Comments
J Holmes
This is almost scary. Fascinating, but scary. Great for cold cases, as long as there is other evidence available. I wonder how they handle those rare people who are genetic chimeras? Wait, that could be a great mystery novel!
Sue Coletta
Great question, Julie. I read that human chimeras only happen with fraternal twins, which is fascinating, but I would guess they’d still have similar characteristics. In the case of a bone marrow transplant, chimeras could cause a problem, especially for the donor. Imagine? You give the gift of life and the recipient kills someone? Hmm, you’re right. This has mystery written all over it. 🙂
Mae Clair
I’m really late, but I’ve been following this case since the news broke. Great informative look at the details, Sue!
Sue Coletta
Thanks, Mae!
patriciaruthsusan
Great post, Sue. It’s one of the most interesting I’ve ever read. —- Suzanne
Sue Coletta
Wow. That’s a huge compliment. Thank you, Suzanne!
Harry Husted
Wow, what an interesting subject. I studied DNA in college and found it truly a marvel. Isn’t it fascinating that you can take DNA and give a basic construction of what that person would look like?That is so cool.
Sue Coletta
Agreed! I just learned about another new advancement in DNA. Stay tuned for an upcoming post on the subject.
JUNE LORRAINE ROBERTS
Absolutely fascinating Sue..thanks!
Sue Coletta
Thanks, June! Big hugs. xo
Michael Helms
Very interesting post, Sue. However, I’ll play Devil’s advocate here: I’m not totally convinced about DNA Phenotyping. It sounds good on paper, but doesn’t it hint a tiny bit at guesswork? DeAngelo might be–and probably is–guilty of these charges. But has Phenotyping been proven without the slightest possibility of error? If this is indeed “the PREDICTION of physical appearance from DNA,” does that not leave open the slightest POSSIBILITY of error? I’m simply curious. And will this stand up in a court of law without a reasonable doubt?
Sue Coletta
DNA Phenotyping is an investigative tool that led to validation through DeAngelo’s DNA. The case gets even more interesting. Today, the DA admitted they also used familial DNA to narrow the suspect list. Now, that’s a slippery slope that many view as unconstitutional.
Harry Husted
Sue, I agree with you and disagree with Michael. Unless Michael is in law enforcement or a scientist, he really doesn’t understand the science or legalities behind such a process. I do and know from talking to an FBI agent, that DNA Phenotyping is an important part of investigative work.
Sue Coletta
Yes it is, Harry. DNA Phenotyping is an amazing investigative tool.
P.S. Michael doesn’t work in law enforcement or within the scientific community. For some, the intricacies of forensics are difficult to grasp and/or believe. Hence why the CSI Effect is poisoning our juries. That’s okay. We’re allowed our own opinions, even if we disagree. 🙂
Harry Husted
Very true. I found playing the Devil’s advocate got me in trouble, so I don’t do it. I do agree that forensics is difficult for some to grasp, especially if they’ve been trained over time to believe anything other than this type of science. Yes, I also agree that we’ve been hooked on CSI. I actually talked to a forensic scientist, who was on one of the CSI shows. He was a consultant for them. He said that CSI does get many procedures right, except for the timeline. Many cases that involve forensics can take weeks not minutes to solve.
Sue Coletta
True. The problem is, not every crime scene has forensic evidence and the jury expects it. If there’s no DNA, for example, they’re more likely to let the defendant walk. It’s a serious problem in this country due to inaccuracies in crime dramas. Ask any law enforcement professional about the CSI Effect and they’ll have A LOT to say on the subject, most of it bad.
Barbara
Hi Sue. Great post. Do you eer consider writing true crime? You do such thorough research.
What I’m curious about is what traits are influenced by environment? I find that idea amazing.
Sue Coletta
Thank you, Barbara! I’ve consider writing true crime many times, but it wouldn’t allow me the freedom I have with fiction. The blog helps feed my craving for true crime. That said, many of my antagonists are based on real killers, sometimes combining a few to create the perfect opponent for my hero. I’ll also read real-world articles for inspiration.
It’s not specific traits, per se. Rather it’s how the environment plays a role to change those traits. For example, a life of booze and drugs will deepen someone’s facial lines, stress can cause us to age faster, etc. The carbon in the air leaves crystallins in the eyes, but they can only be seen after death. I wrote a post about that which may interest you: https://www.suecoletta.com/forensics-radiocarbon-dating-skeletal-differences/
C.S. Boyack
Outstanding post, Sue. Excited about your news at the end too.
Sue Coletta
Thanks, Craig. It was the quickest acceptance letter (five days from submission). Usually I wait weeks for a firm yes with new pub. contract.
Paul Dale Anderson
You did a lot of research, Sue. Great job! Very timely, too.
Sue Coletta
Thanks, Paul! I had to dig deep to find the DNA technique they used. The DA is remaining hush on the specifics while they build their case. Understandable.
UPDATE: They also used familial DNA. Wow. That’s risky to admit.
Garry Rodgers
Fascinating cold case breakthrough, Sue. This phenotyping science is as big a step forward as first employing basic DNA profiling. Seattle police recently released a phenotype sketch on a double-murder cold case where the victims were from our jurisdiction. https://www.seattletimes.com/seattle-news/crime/will-new-dna-sketches-lead-to-killer-of-canadian-couple-during-trip-to-seattle-in-1987/ It’s generated a number of new leads.
What do you make of the Golden State Killer being so active from 1976 to 1981 then being linked to a 1986 offense and then dropping right off the map?
Barbara
I find his inactivity interesting too. I always thought they didn’t stop till caught. But BTK proved that wrong. But WHY stop? The whys of true crime just pull me in. I want to understand what can’t be understood, I guess.
Sue Coletta
Phenotype sketches are amazing tools, and so accurate. I scrolled through a ton of them while researching for this post.
As you know, the Golden State Killer’s extended cooling off period isn’t totally unheard of. BTK’s spanned 20 years. The stolen trinkets allow serial killers to relive their experiences between murders. If he did, indeed, stop, I’m betting the advancement of forensics played an important role. DNA was in its infancy in 1986, and maybe that scared him. Or perhaps having a daughter of his own made him take a hard look at his life (doubtful but possible). It also wouldn’t surprise me if he stayed active much longer than 1986, with a complete change in MO, and LEOs just haven’t made the connection yet. Time will tell. With any luck, he’ll want the credit for his crimes and confess.
Robert Leonard
Fine, about time that animal was caught. Now for all the victims and the loved ones of the victims, for all the scared shitless persons that had to go through that horror let us as a society get this right. Give him his day in court and when all is said and done EXECUTE this animal with extreme prejudice.
Sue Coletta
Nicely said, Robert. I agree.
Margot Kinberg
This is absolutely fascinating, Sue. It makes me wonder how many other unsolved crimes we may be able to solve now. I’m very glad the victims’ families will now have whatever peace comes from knowing who the criminal is.
Sue Coletta
As am I, Margot. Isn’t DNA Phenotyping fascinating? I wasted way too much time on their site, looking at image results. I can’t wait to see what the forensic community discovers next.