I’ve long pondered starting a thread devoted to Zodiac’s apparent fixation with the SF Chronicle. I believe that he read this newspaper religiously and sometimes responded to articles both about himself and about crimes that he was speculated to possibly be responsible for. This was one I had heard of before but was not familiar with. The killing of Robert Michael Salem appears in the SF Chronicle on 4/20/70, showing writing on the wall of the crime scene "Satan Saves- Zodiac". Zodiac then responds by sending a letter on the very same day, upping his body count to 10 while providing no confirming details whatsoever (plausible deniability, IMHO). I’ll get to other examples of Z responding to Chronicle articles but I thought this one was interesting since he ignores a murder in which the perpetrator seems to claim to be Zodiac but offers a denial about his responsibility for the Park Station bombing, which killed Sgt. Brian McDonnell.

http://zodiackiller.com/MyNameIsLetter.html