my opinion – it’s a lot harder to murder someone and get away with it than it is to mail a letter. for the killings, he may have needed to wait for family to be out of town, or for an opportunity to travel for work, he may have had some opportunities but didn’t find any victims during those periods, etc. for the mailings, he could have done all of it from home except dropping it in the mailbox.

i’m still of the opinion (a hunch, really) that he traveled for work and use the weekends during these travel periods to commit the murders and mail the letters.

Since those periods of time are in increments of a certain amount of months, I wonder if the answer could be away on military duty for lengths of time, working out of state, or my personal favorite, locked up in a mental institution for various lengths of time.

Certainly a good topic.

197 Days, just over 6 months

122 Days, just over 4 months

138 days, just over 4 months, not quite 5

Military,Training, schooling, work, institutionalized, etc could all be possible answers. Hard to think he would stay away for that long when he liked the attention so much.

Could have been at sea.

The old merchant marine theory.

It’s hard to tell if there is a true pattern there or not, though. There’s a fair gap between most of his letters, often a month or so. Then we have these longer intervals. Whether the latter are actually different in nature from the former is impossible to say. Perhaps he just got the urge to write every so often – and it varied how often that was.

As for LHR, I don’t think his silence was imposed on him. I simply don’t think it occurred to him to write until BRS. Perhaps he had imagined a different sort of reaction after LHR – and with that in mind, he set to work making sure he would get the right kind of publicity after BRS.

Could have been at sea.

The old merchant marine theory.

It’s hard to tell if there is a true pattern there or not, though. There’s a fair gap between most of his letters, often a month or so. Then we have these longer intervals. Whether the latter are actually different in nature from the former is impossible to say. Perhaps he just got the urge to write every so often – and it varied how often that was.

As for LHR, I don’t think his silence was imposed on him. I simply don’t think it occurred to him to write until BRS. Perhaps he had imagined a different sort of reaction after LHR – and with that in mind, he set to work making sure he would get the right kind of publicity after BRS.

That’s one I forgot about, good possibility

As for LHR, I don’t think his silence was imposed on him. I simply don’t think it occurred to him to write until BRS.

Unless….DARE I SAY IT, he was the Bates letter writer and/or caller in her case, then he already had shown a pattern of writing letters, and calling

Sometimes I think he just didn’t want to fall off the radar.

Unless….DARE I SAY IT, he was the Bates letter writer and/or caller in her case, then he already had shown a pattern of writing letters, and calling

Hehe. Yes.

Could claim that no letter post LHR indicates that he was not responsible for the Riverside letters, though – for the very reason that he did not write after LHR. It doesn’t follow the pattern – until he includes it in the BRS letter, that is. If you look at it in isolation, I still say the silence after LHR indicates a killer who had not yet figured out that he would add a letter writing campaign to his killing ways.

Then again, if he WAS responsible for Riverside he may have, for various possible reasons, considered it a separate deal. He didn’t identify himself as anything like Zodiac in those letters/communications. In fact, I think we have to say that he DID consider it a different deal IF he was responsible for Riverside. He states plainly enough that he started his “collecting of slaves” with LHR, and he doesn’t take credit for Riverside until Avery writes about the connection.

You didn’t offer it as a suggestion so I will raise it: is it possible that, during the times he committed the crimes (1969) and wrote letters ( 1969 – 1974 and beyond), he actually lived out of state and traveled on business? A salesman maybe? Some sort of occupation that required the use of his own car? Maybe lived in a state that actually had snow and didn’t travel during winter months? Where I live our snowy times are between January and March. Been a time or two where we had snow in December and April but rather rare.

Soze

In reading over on the Darlene Ferrin pages, Darlene told her babysitter, and her babysitter told police, that her possible stalker "had just gotten back from out of state." Make of that what you will.

Perhaps he suffered from seasonal-affective disorder and simply couldn’t motivate himself to engage much in "external" activities during the winter months.

A semi-related question …. does anyone know when Berkeley or other area schools ended their semester in Dec. 1968?

A semi-related question …. does anyone know when Berkeley or other area schools ended their semester in Dec. 1968?

At a guess: Around the 20th.

I found an old UC Davis calendar from the mid-60s and the last order of business there was the 20th. Depends how you define it, though.

When would the actual courses taken by Student NN have ended?

Guess: Between the 15th and the 20th.

This is an extremely interesting observation. Just a quick note that Donna Lass disappears in September 1970 and the peek through the pines letter shows up in March 1971, fitting the pattern.

There might be something to this. The distribution per month of the canonical vs non-canonical attacks and letters is different. The canonical events distribution per month of the year is peakier and the non-canonical event distribution is flatter. The canonical distribution shows increased activity in March-April, July, and October, with periods of low or no activity in January-February and May. The only "canonical" event in January is the 1974 Exorcist letter, which I have never liked very much.

Of course, the sample size of non-canonical events is smaller, which may affect the analysis, but one would then expect it to show more variation than the larger canonical set, rather than less.

Interestingly, a canonical plus list which adds Santa Barbara, the CJB related events, the Donna Lass events, and the Radetich murder to the canonical list reinforces the pattern. We know already that there is a strong preference for Z to be active on weekends, at least for attacks. It may be that Z also had strong seasonal preferences.

Canonical events:

Lake Herman Road murders
Blue Rock Springs murders
408 Cipher letters
This is the Zodiac speaking letter
Lake Berryessa murders
Paul Stine murder
Stine shirt letter 1
340 Cipher letter
Fouke Letter
Stine shirt letter 2
My name is letter
Blast letter
Zodiac Buttons letter
Kathleen Johns letter
Mikado letter
Halloween card
Riverside letter
Peek through the pines letter
Exorcist letter

Non-Canonical events

Santa Barbara murders
Cheri Jo Bates murder
Cheri Jo Bates confession letter
Bates had to die letter
Kathleen Johns attack
Radetich murder
Donna Lass disappearance
13th letter
You are next letter
SLA letter
Badlands letter
Red Phantom letter
It’s me letter