Matthew Shepard not murdered for being gay, new book claims Fifteen years after Matthew Shepard was tied to a fence and beaten to death in Wyoming, becoming a powerful symbol for the gay community's fight for hate crimes legislation, a new book claims the college student was murdered for "reasons far more complicated" than being homosexual. Stephen Jimenez's "The Book of Matt: Hidden Truths About the Murder of Matthew Shepard" claims a 13-year investigation - including trips to Laramie, Wyo., and interviews with more than 100 sources - contradicts police testimony and national consensus that the University of Wyoming freshman was targeted by Aaron McKinney and Russell Henderson in 1998 because he was gay. "His aim was to write a screenplay on what he, and the rest of the nation, believed to be an open-and-shut case of bigoted violence," reads a press release accompanying the 368-page book, which hits shelves Tuesday. As a gay man, he felt an added moral imperative to tell Matthew's story. But what Jimenez eventually found in Wyoming was a tangled web of secrets. The Book of Matt: Hidden Things About the Murder of Matthew Shepard Billed as a book sure to inspire dialogue, Jimenez claims his efforts to clearly explain the "misunderstood" crime led him to twenty states and Washington, D.C., as well as into the "deadly underworld of drug trafficking," according to the press release. Who was the real Matthew Shepard and what were the true circumstances of his brutal murder? And now that he was larger than life, did anyone care? Shepard, 21, died five days after the gruesome attack. He was pistol-whipped into a coma while tied to a fence outside the small college town. His death, which quickly became synonymous with anti-gay hate in America, inspired several films, a play and federal hate-crime legislation signed by President Obama in 2009. Jimenez, a veteran journalist, producer and graduate of Georgetown University, defended the book and his "rigorous journalistic standards" when contacted by FoxNews.com on Friday. "I applied rigorous journalistic standards to the reporting and writing of this book, relying on sources ranging from those in the legal system and law enforcement to those who knew Matthew Shepard and the perpetrators personally," Jimenez's statement read. Principal among them were the Shepard prosecutor, Cal Rerucha, who won double life sentences for the perpetrators; lead homicide detective Ben Fritzen; former police officer and drug investigator Flint Waters; and numerous other law enforcement officials from several agencies. I have also included a number of new sources in the book, who are speaking on the record for the first time. Jimenez told The Dish he discovered a key piece of the puzzle in the form of an anonymous letter in formerly-sealed court documents. "Basically the letter was saying that the defense raised by Aaron McKinney's defense team of 'gay panic' was false and the evidence that was cited for that was that Aaron McKinney had been a male hustler, that he was familiar with gay guys in gay bars," Jimenez told the website. It mentioned at first both Aaron and Russell, but as the letter went on it spoke more about Aaron, mentioning that he really did like having sex with gay guys, that he wasn't unfamiliar with homosexuality and the gay world. The Matthew Shepard Foundation, meanwhile, has blasted Jimenez's take, characterizing the book as an attempt to rewrite history. "Attempts now to rewrite the story of this hate crime appear to be based on untrustworthy sources, factual errors, rumors and innuendo rather than the actual evidence gathered by law enforcement and presented in a court of law," the statement reads. We do not respond to innuendo, rumor or conspiracy theories. Instead, we remain committed to honoring Matthew's memory, and refuse to be intimidated by those who seek to tarnish it. We owe that to the tens of thousands of donors, activists, volunteers and allies to the cause of equality who have made our work possible. McKinney and Henderson, both of whom are serving life sentences in Wyoming for the killing, broke their silence on the case in 2004 during their first public interview following the attack. They said they were motivated by the prospect of robbery to feed a methamphetamine binge rather than violent homophobia. "He was pretty well-dressed, had a wallet full of money," McKinney told ABC's 20/20 of meeting Shepard at a bar. All I wanted to do was beat him up and rob him ... Seemed like a good idea at the time. Being strung out on meth for days was the motivation for killing Shepard, McKinney said. "It's not because me and Aaron had anything against gays or any of that," Henderson said, adding that he thought if he could keep McKinney drinking that night he'd forget the ominous plan. Shepard was sitting at the bar when McKinney and Henderson arrived. At one point, McKinney asked Shepard for a cigarette. "He said he was too drunk to go home and then he asked me if I'd give him a ride," McKinney said. Once inside the truck, McKinney claimed he and Henderson realized Shepard wanted sex in return for giving them drugs. The duo decided to rob Shepard instead, McKinney claimed. McKinney said Shepard grabbed his leg and he then struck the college freshman with his gun as he demanded money. The vicious beating continued well after Shepard forked over his wallet. "Sometimes when you have that rage going through you, there's no stopping it," McKinney said. I've attacked my best friends coming off of meth binges. McKinney's attorney, Dion Curtis, said in 2004 that drugs and money rather than sexuality had long been considered the primary motives for the killing. Prosecutor Cal Rerucha has also said the case was too complex to be merely categorized as a hate crime.