The only report I have is already out there. It states the call was traced by PT&T. There would have been no need for a trace had Zodiac provided the number of the phone booth. And had the tracing begun when Zodiac was speaking with Nancy, the call would have ended long before a trace could have been completed by PT&T. Which means the tracing process had to have begun much earlier in the call.

IMHO, the most likely scenario is Zodiac dialed 0, got the PT&T operator, and said something along the lines of "I just killed some people, give me the police." The PT&T operator would have then begun the tracing process, and probably attempted to get more info. Zodiac would have refused to give his name or number, and eventually would have been patched through to Nancy.

IMHO, the most likely scenario is Zodiac dialed 0, got the PT&T operator, and said something along the lines of "I just killed some people, give me the police." The PT&T operator would have then begun the tracing process, and probably attempted to get more info. Zodiac would have refused to give his name or number, and eventually would have been patched through to Nancy.

Sounds as likely as anything.

So that is that. There are no clues to be found. The operator stayed on the line per Pacific Telephone and Telegraph practices in case they were needed during emergency calls. So everything was as it should have been.

They did not stay on the line once the dispatcher took over. That would have been against the law and a fire-able offense.

It’s important to put into context some details here. For one, the call was routed to a telephone exchange center in Ukiah, CA. This was a small building located on the intersection of South School Street and West Church Street. There would have been 4 to 8 operators working the switchboard with one chief operator literally walking back and forth behind them, monitoring everything going on. This chief operator was Betty Main who is mentioned in the police report.

The fact that the call was routed so far away from Vallejo was unusual, but a possible explanation is that it was the early morning after the 4th of July and call volume might have necessitated that.

Yes, exactly that is how it works. I retired from the phone company and it is hard to explain the old ways they did things. The operators used patch cords on the board to connect the different carriers. My cousin became an operator when she was still in high school. She retired from Southern Bell after 35 years, ending her career as a splice service technician. They have Alexander Graham Bel’s lab in Boston. That phone that called San Fransisco in 1909 still works and can make a phone call with slight adjustments. We built things to last a fixed them properly years ago. Now adays I do not know.

The only report I have is already out there. It states the call was traced by PT&T. There would have been no need for a trace had Zodiac provided the number of the phone booth. And had the tracing begun when Zodiac was speaking with Nancy, the call would have ended long before a trace could have been completed by PT&T. Which means the tracing process had to have begun much earlier in the call.

IMHO, the most likely scenario is Zodiac dialed 0, got the PT&T operator, and said something along the lines of "I just killed some people, give me the police." The PT&T operator would have then begun the tracing process, and probably attempted to get more info. Zodiac would have refused to give his name or number, and eventually would have been patched through to Nancy.

Now we are getting into the semantics of the word “trace”. That’s not really a road I’m interested in traveling down.

I feel “trace”in this case, can simply mean “location identified”.

Still, if you’re right, that doesn’t explain how a trace was begun PRIOR to Slover speaking with Z. PT&T could only initiate a trace on a line if it was requested by law enforcement. An operator or supervisor could not trace a line without authorization, and the tracing that you describe (long, intricate line tracing done while the line was open) was not conducted by the switchboard operator, but at another location (central office).

So, we can either believe that the Zodiac had a long, disturbing conversation with the operator who then illegally requested a line trace that just happened to conclude 7 minutes after the call to Slover.

Or the answer is much simpler and Zodiac gave her the number and she or her supervisor used reverse directory to find the location or she saw it was a pay phone on her switchboard and cross-referenced the four digit display next to it to a flipchart they had next to them that indicated its location.

I’m not trying to be argumentative. I’m only offering what I know and applying it to the situation here. If you have contradictory information, please share.

PT&T could only initiate a trace on a line if it was requested by law enforcement.

That is the opposite of what I’ve learned.

The operator could not trace a call from there. An inductive pin tap would need to be placed on the POTS line at the frame. There is absolutely no way they could trace a call that fast. I set up all of CALEA links for New England. They need a technician to come into the central office and they work 8-5. It would take about 10-15 minutes to set up a phone tap. The tap must be requested by law enforcement. The operator simply locked up the line and they traced it out in the morning. Law enforcement connect to an internet link that allows access to the ATT 5e switch or the Nortel DMS Switch. They do not request the trace anymore. They have the CALEA access now the FBI can listen on monitor to the conversations going into any telephone. I set much of it up.

The telephone company can not tap any phone without a court order from law enforcement. The cops need a warrant to go in to the CALEA links as well.

We are talking about tracing a location, not tapping or monitoring conversations. And it was way back in July 1969, with a company that back then didn’t legally need to cooperate with homicide investigations.

Had Zodiac not said something damning to Mrs. Johnson, there would have been no reason for her to stay on the line after patching Zodiac through to the police. But she did stay on the line, all the way until he finally did say something damning, way at the end of the call.

I had half a dozen former PT&T employees from the 1960s who independently and emphatically said that a line trace could not be initiated without a request from law enforcement when I asked – one of which worked in Hayward, CA which is just south of Vallejo.

Tom, how did you confirm that she stayed on the line? I have tracked down Betty Main, but have been unable to locate Mrs. Johnson. Have you spoken with her?

With a trace they would need to trace from the crossbar switch to the main distribution frame. They would dispatch a tech to run to a loop cross on the pair at the phone booth. They would look in line records file and find the address of the physical termination at the payphone. The outside tech would look for a loop on the pair at the frame. That is the only way to know for certain where the phone line actually runs. To complete a trace all these steps must be done. It used to take time years ago.

Tom, how did you confirm that she stayed on the line?

How else could she have known the location of the phone booth would be of interest to the police?

I had half a dozen former PT&T employees from the 1960s who independently and emphatically said that a line trace could not be initiated without a request from law enforcement when I asked – one of which worked in Hayward, CA which is just south of Vallejo.

Hayward is two counties away from Vallejo. I have no idea what what was protocol in Hayward.

The police report show Nancy Slover received the call at 12:40. It then says at 12:47 Mrs Johnson called to report the call had been traced. So it was only seven minutes after he hung up.

The police reports don’t say anything about the police contacting the phone company to perform a trace, seems like that would be in the report if they did.

So it sounds like from that, the phone company performed the trace on their own without a request by the Vallejo PD, but we might not have the full story there.

I think the meaning of a call trace might be muddled here. The office in that town was relatively small. They would see the call up on the switch by lights on the bay indicating a busy line. As long as the operator has the patch cord plugged into the board the switch will hold its position because the relay is closed at the switch interface. A telephone man could find which pair the switch was connected to and look up the line record and get the address of the payphone.So in fact they identified the telephone line within 7 minutes using telephone company records.

I wonder if the operator recognized Zodiacs voice. Crazy, drunk,or lonely old people will call the phone company and stalk the operators. Perhaps they knew the voice as somebody who called up frequently and made them nervous.

I had half a dozen former PT&T employees from the 1960s who independently and emphatically said that a line trace could not be initiated without a request from law enforcement when I asked – one of which worked in Hayward, CA which is just south of Vallejo.

Hayward is two counties away from Vallejo. I have no idea what what was protocol in Hayward.

My point was that this particular person worked as an operator for PT&T in the Bay Area at the same time Zodiac placed his call to Slover. It’s not like someone from San Diego in 1980.

But if you want to be pedantic about it, Hayward is the same distance from Vallejo as Lake Berryessa, only ten miles farther away as Presidio Heights, and less than an hour drive from Mount Diablo.

Different municipalities would not have different protocols. They were all governed by PT&T regulations which, as you have pointed out, were ironclad.

Still, This is good. I enjoy this respectful give and take. It’s possible to disagree without being disagreeable. Hopefully, the more this is discussed, the more layers we can peel off the onion.

I’m going to continue talking to the PT&T folks and trying to track down Mrs. Johnson.