The true identity of the Zodiac Killer is still unknown to this day, but many suspects have been considered.
Arthur Leigh Allen
This is one of the most famous Zodiac Killer suspects. Allen was a convicted child molester who knew one of the victims, and he also resembled a police sketch of the killer. However, despite being investigated and having his home searched, he was never charged with the murders, and died in 1992.
Richard Gaikowski
Gaikowski was a writer and journalist who worked for a radical newspaper in San Francisco during the same period that the Zodiac Killer was active. He was considered a suspect by some investigators, but there was never enough evidence to charge him with the crimes. Gaikowski died in 2004.
Lawrence Kane
Kane was a former mental patient who was briefly considered a suspect in the case. He had a history of mental illness and had reportedly made threats to kill people. However, he was never charged with the murders.
Ted Kaczynski
Kaczynski, also known as the Unabomber, was a notorious domestic terrorist who carried out a bombing campaign that killed three people and injured many others. Some investigators have suggested that he may also have been the Zodiac Killer, but there is little evidence to support this theory.
Ross Sullivan
Sullivan was a mentally ill man who worked at the Riverside City College where Cheri Jo Bates, a possible Zodiac victim, was a student. He reportedly had a fascination with knives and violence, and some investigators have suggested that he may have been the killer. However, there was no concrete evidence linking him to the crimes.