Ted Kaczynski, the domestic terrorist and mathematician known as the Unabomber, was investigated for possible Zodiac connections in 1996. He worked in Northern California around the time of the murders and, like the Zodiac, had an interest in cryptography and pressured the press into publishing his writings. Both the FBI and San Francisco Police Department ruled him out based on fingerprint and handwriting comparisons and his documented absence from California on certain dates of known Zodiac activity.