Man Claims Dad Was Zodiac Killer in New Book Gary L. Stewart says he came to conclusion while searching for biological father By Kate Seamons, Newser Staff Posted May 13, 2014 6:18 AM CDT 15 comments Comments A sketch of the Zodiac killer based on witness testimonies. (Wikimedia Commons) (Newser) – It's an explosive claim shrouded in an unbelievable amount of secrecy. Gary L. Stewart alleges that a dozen years of research have led him to the conclusion that his father was the Zodiac Killer—and HarperCollins is publishing a book to that end today. New York broke the news yesterday, pointing out that a sea of HarperCollins staffers have managed to keep the lid on The Most Dangerous Animal of All, which as of yesterday appeared on the publisher's website, without cover art or mention of the words "Zodiac Killer." But it does explain that Stewart, the VP of a Baton Rouge cleaning company, came to his conclusion after launching a search for his biological father shortly after his birth mother made contact with him. It also claims that he unearthed "forensic evidence" among the "host of clues" he found. New York spoke with HarperCollins publicist Tina Andreadis, who shines a little more light on the origins of the book, which the publishing house's lawyers felt "was legally sound" upon review, she says. Who didn't review it: The San Francisco Police Department, which the book alleges "knew more than they’re willing to admit." The killings took place in Northern California beginning in the late 1960s, and Andreadis notes that Stewart's father has both a resemblance to sketches of the killer and a criminal record for misdeeds like bad checks in San Francisco. Slate points out that the book is coming out of a pretty reputable publishing house, though one that has had its "sensationalistic" turn; Slate notes it was where OJ Simpson's If I Did It was supposed to be published. It's certainly not the first book claiming to have cracked the case—nor the first time someone pinned the crimes on his or her dad.