The Case of the Ciphers – Who is the Zodiac Killer?


Renee Pi, Journalist

The Zodiac Killer- an infamous serial killer that terrorized the Bay Area in the late 1960s, killing at least 5 people. Recently, a cold case team claimed they figured out his identity. Who was he, really? What did he do?

The first letters were sent on August 1st, 1969 to editors of popular newspapers in the Bay Area, including the San Francisco Examiner. “Dear Editor: I am the killer of 2 teenagers last Christmas at Lake Herman,” the letter began. This was followed by details of the murder that only the killer could have known. He then went on to threaten more attacks if the letter wasn’t published on the front page of newspapers. The letters were signed with a circle with a cross through it, a symbol which would soon gain notoriety throughout the country as the Zodiac Killer’s signature. To top it off, the letters were accompanied with a three-part cipher, which the Zodiac Killer claimed contained his name. 

The second letter taunted the police and FBI for not being able to solve his cipher or catch him. Nevertheless, the cipher was solved a few days later by a high school teacher and his wife. Contrary to the Zodiac Killer’s claim, the cipher did not contain any information on his identity. Instead, it consisted of a poorly written message, describing how much he enjoyed killing. By now, he had four confirmed attacks, the first of which was in 1966. The victims, in chronological order, were an 18-year-old college student in Riverside (1966), a teenage couple in the remote northern area of San Francisco (1968), and two other couples a year later in 1969 (The man targeted in the first attack survived). Several days after the last killing, a taxi driver was murdered. A new letter contained details of the murder and more threats, similar to the first. The 5th murder was the last confirmed one, although it is now believed Cheri Jo Bates was murdered by the Zodiac Killer as well. 

From that day on, more letters occasionally came, including information about murders the Zodiac Killer claimed responsibility for and numerous ciphers. The “My name is…” cipher also known as the z13 is one of his most boggling ones. It consists of 13 characters, and still hasn’t been solved to this day! However, it is unlikely that the Zodiac Killer’s name was actually on the cipher, as he was a man of mystery. Then one day, in 1974, the letters stopped arriving. Despite this, some think the Zodiac Killer still remained active during the 1980s. 

Recently, a team claimed that they discovered the identity of the Zodiac Killer. They believe that the Zodiac Killer is a man who died in 2018, named Gary Francis Poste. Poste was a veteran of the United States Air Force. He was from eastern California and was accused multiple times of being the Zodiac Killer. According to a San Francisco newspaper, the San Francisco Chronicle, a relative accused Poste of being the Zodiac Killer 6 years ago. The relative also says that Poste lived in the town of Groveland at that time. The Chronicle contacted the Police in the Bay Area, but they dismissed the accusation, as Poste had no connection with being the Zodiac Killer.  According to the same paper, he was also accused by his former daughter-in-law, Michelle Wynns, who says she moved away from Poste to get away from his threats. 

The Zodiac Killer has always inspired fear. He became infamous for sending letters containing ciphers and cryptograms, some of which haven’t been solved to this day! Now, a cold case team believes the Zodiac Killer to be Gary Francis Poste. However, since no family members could be contacted, the case remains open, and the search for more information about him continues.


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