Waiting on an Envelope

The Symbol on the Blackboard

Mara: Jacob Lehman remembers a kitchen chalkboard. He was a boy, reading Susan Cooper's fantasy novel The Dark Is Rising, where the young hero is protected from evil by 'a circle, quartered by a cross.' So he doodled it. In his Substack essay, Jacob writes that his father, Peter, erased it, followed him into a bedroom, shoved him against a wall and shouted at him, demanding where he saw that symbol and what book. And then Peter banned him from ever drawing it again.

Eli: That symbol, Jacob says, looks like the Zodiac Killer's signature. A listener sent us his essay with a short note: fascinating read. Underneath that note sits a real question. Does the essay actually tie his father to the Zodiac murders? Today's angle is the collision between family trauma and forensic reality in an unsolved serial murder case.

Mara: Jacob Lehman wrote that down. In the late 2000s, in therapy using a technique called EMDR, he says he recovered memories of childhood abuse. And in them, he says, he saw his father taking part.

Eli: He doesn't call those memories Zodiac evidence. The chalkboard is the one he does.

Mara: That case went public on August 27th, 2026. The headline: 'My dad may be the Zodiac Killer and there is physical evidence that may link him to the murders.' Jacob took his allegations to authorities as well. The core of it is a timeline. In 1969, he writes, Peter moved to the Bay Area as a 25-year-old postdoctoral chemistry student at UC Berkeley, working at Berkeley National Laboratories. The first murder Jacob ties to the Zodiac came shortly after. And he believes his father matched the police drawing of the suspect, going by old photographs he remembers but doesn't have.

Eli: Deborah Perez said her father looked just like that drawing when she saw it on television in 2007.

Mara: So, memories of pictures. Which puts a lot of weight on the dates.

Eli: Then here's what the dates have to fit. Police tie seven victims to the Zodiac across Northern California in 1968 and 1969, and five of them died. Those are the canonical attacks. The killer himself bragged about far more, up to 37. The first killings came on December 20th, 1968. Two high school students, sixteen and seventeen, shot dead on Lake Herman Road.

Mara: So the canonical attacks are the ones police actually pinned on him, not the ones he boasted about.

Eli: Pinned through the letters and the scene evidence. After a San Francisco cab driver was shot in October 1969, a letter reached the Chronicle with a scrap of his bloodied shirt inside.

Mara: And Jacob puts Peter's move in 1969. Lake Herman Road was the December before.

Eli: His timeline starts from the first murder Jacob himself counts as the Zodiac's. Beyond the calendar, Mara, his case so far is a chalkboard, a move to Berkeley and a remembered face, and anything harder than that would have to come from somewhere else.

Memories and Memoirs

Mara: What else he holds, by his own account, is very little on paper. No handwriting samples from Peter, no records, no photos from the era. He's said his father's handwriting resembles the letters, but he has nothing of Peter's to set beside them. What he does have is a reading of the letters' tone. They remind him, he writes, of Peter's 'aggressive egotism, his need to be feared for his violence, his need to feel intellectually superior, his obsession with puzzles and riddles.'

Eli: One commenter pointed out the letters are published in facsimile. Handwriting, at least, is checkable.

Mara: And that's where the boy at the chalkboard comes back, grown now and estranged from his father. He called reaching his conclusion 'fairly devastating.' So he's asking for something that doesn't lean on memory at all. A hair, reported found under a Zodiac stamp back in 2002. If chromosomal DNA, the inherited genetic blueprint that links a parent and child, can be extracted from it, and he's right, Jacob says it would be roughly a 50 percent match with his and his brother's DNA. He's raised mitochondrial DNA as another route.

Eli: That assumes the hair holds usable DNA. No one in authority has announced that it does.

Mara: For Jacob, the timeline, the resemblance and that shove at the chalkboard add up to grounds for a formal investigation.

Eli: Forensic analysts and case researchers read the same pile as interpretation and memory, with no DNA or fingerprint match behind it. And they've watched this shape before. In 2014, an adopted man published a bestseller, The Most Dangerous Animal of All, naming his late biological father, a rare book dealer, as the Zodiac. He said the victims resembled his mother, and that his father's handwriting was 'virtually' the same as the killer's.

Mara: The Lake Berryessa survivor was skeptical. Someone, he told CNN, is always stirring the pot.

Eli: Then the handwriting came apart. One key sample was the writing on a marriage certificate he'd pinned on his father. Researchers on a Zodiac forum tracked down handwriting from the reverend who performed that marriage. It took them about three days. The writing on the certificate matched the reverend.

Mara: Jacob's bet is the one thing that book never had, a lab result. Everything now turns on what a test of that stamp could actually show.

The Forensic Wall

Eli: That handwriting claim sank after researchers in Tom Voigt's forum matched the writing to the reverend's. Jacob's test runs into something older. In 2002, San Francisco police did get DNA from saliva under a Zodiac stamp. But only a partial DNA profile: a few pieces of a genetic fingerprint instead of the whole thing. Pieces like that can rule a person out. They can't point to one. An inspector said at the time it wasn't enough to run against databases of known criminals. And nobody's shown that saliva even came from the killer.

Mara: So a test on Jacob's family could clear Peter. It could never name him.

Eli: That's the wall. No complete Zodiac profile exists anywhere. One researcher, talking about family-tree methods, put the limit of a partial one simply: 'They wouldn't be able to narrow it down to a single family unit.' And Jacob's backup, mitochondrial DNA, is genetic material handed down the mother's line, the kind often pulled from hair.

Mara: So the chalkboard stays a memory, with nothing in a lab to meet it.

Eli: Every suspect has hit the same wall. No one has ever been charged. The best-known suspect died of a heart attack in 1992, before a decision on charging him was made. The year before, he'd told an interviewer: 'The only thing in my favor is, I've never killed anyone.'

Mara: And that's the backdrop Jacob's remembered photographs land on. When one author started digging into this case, there were 2,500 suspects to sift through. A police spokesman put it bluntly in 2014: 'We've gotten reports over the years from people who don't pan out.' Looking like a composite sketch is notoriously unreliable, and calling a relative abusive or controlling doesn't connect him to specific crimes. A former FBI investigator who fielded calls like these described how they tend to go: 'Then what they say doesn't fit the location of the crime or the time or other details.'

Eli: They still look. In 2014, police said homicide investigators would 'take a look at' that book's claim.

Mara: So Jacob's report joins a very long pile, Eli, and who is still working through that pile today is its own story.

The Living File

Eli: Officially, the case is open. Nobody has ever been arrested or convicted. And it's not a federal case. It belongs to the local Bay Area departments, with the FBI supporting the handwriting, fingerprint and cipher work, the same supporting role it played in 1969. The tips haven't stopped, either. As of May 2026, San Francisco police said they were getting three or four Zodiac tips a week.

Mara: Three or four a week, and Jacob's essay arrived on top of that in August.

Eli: Vallejo police tried something newer in 2018. They sent Zodiac envelopes to a private lab for DNA testing and forensic genetic genealogy, which matches a detailed DNA profile against public family trees to trace relatives toward a name. No breakthrough has been announced. As of 2026, the department still counts its old suspect while looking at others. A San Francisco inspector said it plainly back in 2004: 'If there's any realistic hope of solving the case, it would be from the physical evidence that we have.'

Mara: So for the listener who called the essay a fascinating read: it holds memory, a move to Berkeley and a remembered face. Nothing physical or on the record ties Peter Lehman to the Zodiac murders.

Eli: What would change that is specific. Any public word from Bay Area police on Jacob's report. And what Vallejo's 2018 lab work finally shows.

Mara: The boy drew that circle and cross from a book where it kept someone safe from evil. Whatever his father's fury meant, the case it points toward is still waiting on an envelope, not a memory.

Eli: Dig into canonical attacks.

Mara: And stay with us on law and justice.

Eli: Thanks for spending this time with us. I'm Eli.

Mara: And I'm Mara. Until next time, this has been Angle.