Donald L. Cheney was a former friend of Arthur Leigh Allen. In 1971 he reported to Manhattan Beach police that Allen had, in a conversation he dated to no later than January 1, 1969, spoken of a desire to kill people, of using the name “Zodiac,” and of fastening a flashlight to a firearm for nighttime aiming. According to the sources, Cheney’s account was a major early driver of the suspicion against Allen.
In the 2002 partial-DNA comparison conducted by the San Francisco Police Department crime lab, Cheney was tested alongside Allen against the profile drawn from Zodiac letter stamps; neither matched, and both were excluded as DNA contributors.