AUSTIN, TX --A massive 2008 raid on a Texas polygamist ranch was triggered by "reckless" investigators who didn't verify calls to a domestic abuse hotline that proved to be a hoax rather than cries for help from a battered teenage mom claiming to be pregnant again, attorneys for a convicted sect member said Wednesday. That raid led to bigamy and sexual assault charges against 12 sect members -- including leader Warren Jeffs -- and triggered one of the largest child custody cases in U.S. history. For the first time since then, Texas prosecutors Wednesday defended one of their convictions to an appeals court. Michael Emack, 60, pleaded no contest last year to charges of sexually assaulting a 16-year-old girl. His attorneys asked the 3rd District Court of Appeals to throw out the conviction on the grounds that Texas authorities omitted key details on the search warrant application that got them inside the Yearning for Zion ranch. At the heart of the appeal: that state investigators never told the judge who signed the search warrant that calls alleging domestic abuse came from a blocked phone number, and that a shelter worker gave the girl "multiple-choice options" of what the name of her husband might be. Authorities also failed to first complete basic police work like checking whether a "Sarah Barlow" really existed before asking for the search warrant, said Robert Udashen, Emack's attorney. Authorities suspect that a woman in her 30s living in Colorado made the calls to the shelter. "While it may make people feel good to say we have to save this poor, abused girl, that's not the law," Udashen told the court. The three-judge panel likely won't issue a ruling for several weeks. The case is the first appeal involving a convicted sect member since the April 2008 raid, and the Fundamentalist Church of Jesus Christ of Latter Day Saints will watch closely for the ruling. A victory for Emack could unravel the convictions of six other sect members, and affect five others still waiting for trial, including Warren Jeffs, the ecclesiastical head of the organization. The Texas attorney's general office has not lost a criminal case against sect members since the state raided the ranch. Prosecutor Eric Nichols told the court that both shelter workers who took the phone calls and Texas Rangers had every reason to believe the claims of abuse were really coming from inside the ranch in rural Schleicher County. "The Schleicher County sheriff said that in his experience, persons who live at the ranch blocked their call," Nichols said. Nichols said the trial court already upheld the search warrant during exhaustive hearings involving both sides. State District Judge Barbara Walther has overseen every criminal trial stemming from the raid, which temporarily swept up more than 400 children into state custody. Emack is serving a seven-year prison sentence. Not once during the hour-long hearing did the issue of Emack's guilt or innocence surface. Arguments instead narrowly focused on the legwork by investigators leading up to obtaining the search warrant, which triggered a six-day sweep and the state seizing some 900 boxes of evidence from the ranch. Jeffs, who was extradited to Texas last year, awaits trial in a Schleicher County jail. His trial on charges of bigamy and sexual assault appears unlikely to begin anytime soon, as Walther has yet to even rule on significant matters such as where it will be held. The court has entered a not guilty plea on his behalf.