The Solution of the Zodiac Killer's 340-Character Cipher

Sam Blake, writing at Wolfram Blog: The Zodiac Killer (an unidentified American serial killer active during the 1960s and 70s) sent numerous taunting letters to the press in the San Francisco area with regard to a local murder spree. In these letters, the killer took responsibility for the crimes and threatened to commit further murders. He also included three ciphers, each containing one-third of a 408-character cryptogram. The killer claimed that this cryptogram would reveal his identity when deciphered. The killer sent the fourth and final cipher (discussed in the linked post) to the San Francisco Chronicle after the 408-character cryptogram, deciphered in 1969, did not reveal the killer's identity.

In 2020, Melbourne, Australia, had a 112-day lockdown of the entire city to help stop the spread of COVID-19. The wearing of masks was mandatory and we were limited to one hour a day of outside activity. Otherwise, we were stuck in our homes. This gave me lots of time to look into interesting problems I'd been putting off for years. I was inspired by a YouTube video by David Oranchak, which looked at the Zodiac Killer's 340-character cipher (Z340), which is pictured below. This cipher is considered one of the holy grails of cryptography, as at the time the cipher had resisted attacks for 50 years, so any attempts to find a solution were truly a moonshot.

Rambling and pointless learning.

[Ostracus]

That it's possible to keep a secret for fifty years even with our technology and knowledge.

Re:

[mysidia]

The cipher might be a cruel joke on those who tried to break it with no actual secret to be found at all... I'm imagining 3 scenarios:

1. The plaintext would be something like "Gotcha" or a longer equivalent, rather. Just because they SAID it would reveal the identity of its author does Not mean they were telling the truth - there could be a valid message that basically says nothing or contains the mad ravings of the author, and move on to number 2 scenario:

2. Its random garbage with a message that

Re:Rambling and pointless summary

[hey!]

Comparing the only semi-coherent prose style of the summary with decrypted ciphertext... Perhaps it's a confession?

Re:

[Anonymous Coward]

This story is a dupe (and a very old one). The tl;dr version: After 51 years we have discovered that the Zodiac Killer used an extremely complex code, just so he could send a lame, meaningless message, with misspelled words.

i hope you are having lots of fun in trying to catch me
that wasnt me on the tv show
which brings up a point about me
i am not afraid of the gas chamber
because it will send me to paradice all the sooner
because i now have enough slaves to work for me
where everyone else has nothing when the

Re:Rambling and pointless summary

[gosso920]

P.S. Be sure to drink your Ovaltine.

Time To Start A Rumour

[theshowmecanuck]

The solution is only a hidden cipher to a message revealing who the killer really is.

Re:

[ArchieBunker]

I'm a believer in the theory that the killer was drafted and sent to Vietnam where he was killed in action.

Re:

[theshowmecanuck]

Never heard that one. Mind you, I never really followed this. :)

Re:

[alvinrod]

I'd never heard that theory either. Maybe someone should tell Edwin Starr to release a new cut of his number one single. Might be kind of hard to fit it in and match it up to the beat, but I think if you took out a few of the "Huuuhhs" and "Yaehhhs" you could probably squeeze it in.

Re:

[theshowmecanuck]

Hold it. Is that a rumour? Oh whoosh is it?

Re:

[RockDoctor]

Like a serial killer wouldn't volunteer to be paid to murder people abroad?

Though I I suppose he wouldn't have liked the military's attitude of dehumanising the people they're going to kill. "I don't want to kill 'Gooks', I want to kill PEOPLE!"

Also - what's to stop him (or her, but most likely a him) from having stayed there to enjoy a killing spree with less interference from the cops?

I've not followed USian mass-murderers either.

Lame.

[Gravis Zero]

Not only is this a dupe (an old one at that) but the link doesn't even show you the fully decoded message. How lame.

They completely missed the hidden message

[smooth wombat]

After all that effort, they miss the hidden message which is most the most important part.

Be sure to drink your Ovaltine.

Re:

[bugnuts]

Burma

Re:

[sysrammer]

Shave

(I didn't want to. I *had* to!)

Nope

[Aighearach]

If they had deciphered it, the summary would include the message.

Since it doesn't, it is clear there is something wrong with the claim, and it is just clickbait.

Re:Nope

[imidan]

FTA, the deciphered message (with a few spelling corrections):

I hope you are having lots of fun in trying to catch me that wasnt me on the TV show which brings up a point about me I am not afraid of the gas chamber because it will send me to paradise all the sooner because now I have enough slaves to work for me where everyone else has nothing when they reach paradise so they are afraid of death I am not afraid because I know that my new life is

From what I can tell, it ends abruptly like that. The decryption was confirmed by the FBI cryptanalysis unit.

nix

[EkriirkE]

Is there substance to this post? Seems like it's just filler. It mentions stuff without saying anything

Re:

[war4peace]

RTFA.

Re:

[laxguy]

never.

Interesting

[ArhcAngel]

What a coincidence...Ted Cruz just announced a trip to Melbourne.

Serial killer versus cops

[fermion]

I was reminded recently how many serial killers theyâ(TM)re were in the 1960s and 1970s. What was remarkable is how many of them completely evaded detection, it wasnâ(TM)t our advances in forensics or computers, it was the prejudice and laziness of police. All to often these were people, often teens, that police just assumed has run away or died of a drug overdose. In many cases it was the taunting or an accomplice that alerted the public and forced the police to pretend to do something.

Re:Serial killer versus cops

[LatencyKills]

If there are some statistics that say that there are fewer serial killers now than in the 70's, I'm not aware of them. The same prejudices exist. There remain marginalized members of society (though calling them that is a stretch) who live and die without anyone noticing. The only thing that has changed in the past 30 or so years is our amount of interconnectedness, so that cases of some relative turning up dead decades later when everyone had thought they had simply "moved out west somewheres" are much lower. It perhaps means serial killers have to be more selective to evade detection, not that they have to stop killing or that we're catching more of them.

Re:

[onepoint]

>>It perhaps means serial killers have to be more selective to evade detection, not that they have to stop killing or that we're catching more of them.

the later, it seems with DNA kit's and other systems, catching people that commit multiple killings has become easier in the sense that they are caught faster than ever before, usually within 2 years or less. and lot's of cold cases have become solved with families finding out that "dad was a serial killer" ( I'll have to find that one again to cite sou

Re:

[theskipper]

In retrospect, bet that would have impressed the kids even more if I told them dad was a serial killer rather than an astronaut. Live and learn.

Re:

[onepoint]

trying to find that specific mention about families being informed.

Did find data that validates more of what I said https://www.bustle.com/life/11... [bustle.com]

when I find the other I will post it.

Re:

[onepoint]

this remark is a troll.
most genetic databases are rather good.

Re:

[known_coward_69]

most serial killers were very smart and probably genius level intelligence

most police aren't smart and most police work is repetitive work to uncover a small piece of evidence in a pile of junk

most serial killers were caught by making stupid mistakes or being ratted out by friends or family, not by smart cops

Re:

[garyisabusyguy]

Recent dna based attests do not show genius at work, just off duty cops getting their thrills by killing civilians, one was even a 'protection officer' at Berkeley

Re:

[alvinrod]

Sounds like a bit of survivor bias because idiots don't get away with the first murder they commit. Anyone who can get away with enough to be considered a serial killer is clearly a few steps ahead of the authorities. Of course you have to consider the people who commit all of their murders in a way that never connects any of them to each other.

I was curious about this so I looked into it. There's someone who's been researching and compiling data on serial killers for several decades now who publishes th [fgcu.edu]

Re:

[nitehawk214]

most serial killers were very smart and probably genius level intelligence

Citation fucking needed, there.

Re:

[medv4380]

A couple of factors influence that view. Since a lot of serial killers are found a decade or more after the fact it's always going to look like serial killers are more prominent in the past. It's not always clear that murders are actually serial killers until they're caught. News has also changed, they try not to sensationalize these things too much because when they do they can create a lot more copy cats. Remember that BTK killer did his crimes in the 70s and 80s but was caught in the 2000's

Re:

[rahmrh]

Also there are way too many camera's around, so it becomes much harder to evade detection.

The camera's from the retail store's around here caught a guy who if not caught would have almost certainly be a serial killer now.

So that leaves about the only viable serial killers ones killing random hitchhikers and such were there are no cameras around. But even with that the cell phone pings are probably going to catch you if you were dumb enough to have one with you. And if the victim had a cell phone, that ma

Re:

[RockDoctor]

How, if they "completely evaded detection", do you know they (whoever they were) were a serial killer?

Our most prolific serial killer [wikipedia.org] evaded detection for 28 years. Unless, of course, he had earlier victims for whose killing(s) he has "completely evaded detection".

Missing Letters

[bill_mcgonigle]

The cipher seemingly lacks the letters: J K Q X Z

Assuming one can discount X and Z as very low frequency - did any of the suspects have initials using J, K, and Q?

Looking at this suspects list [fandom.com] shows one "Kjell Qvale". Wikipedia reports [wikipedia.org] that he was a car importer in the San Franscisco area who bought a "significant stake" of Jensen Motors.

It seems that he was already a popular suspect [insidehook.com] who lived near one of the victims [jalopnik.com] and was probably seen on the night of the murder.

The article says he died in 2013.

Of course this is a tenuous stretch, but when a killer says that the encoded message will identify him, it's probably true given the typical personality profile of a serial killer.

The researchers say that the decoding did not identify him, but as Miles Davis instructed, "the music happens between the notes."

Don't reward murderers with publicity

[hackertourist]

It seems to me some serial murderers crave notoriety, and American media are all to willing to accommodate them. Society would benefit from something like Greg Benford's Moron Decree [archive.org]: never identify serial killers to the public. Call them Moron #[serial number] instead.

World class trolling right there.

[BAReFO0t]

Write some nonsense. Tell people it's a ciphertext. That it will reveal your identity.
And the morons will obsess wasting fifty years over the damn red herring instead of actually trying to find out who you are.

Truly deserving of a *slow clap*.

Earl Van Best

[otherPerry]

Earl Van Best, The name is encoded in the cypher solution, almost in the shape of the gunsight/ gothic cross symbol. VAN is the simplest to see, column4, row2 is the start.
      . V .L .R
    . A ._S__ .A
_N __._T._.__ E
_=_ __ B

          E