AUSTIN (AP) – Prosecutors plan to ask an appellate court Wednesday to uphold the sexual assault conviction of a polygamous sect member in the first appeal stemming from the 2008 raid of a West Texas ranch — a massive sweep that set off one of the largest child custody cases in U.S. history.

Michael Emack, 60, pleaded no contest last year to sexually assaulting a 16-year-old girl and was sentenced to seven years in prison. The Fundamentalist Church of Jesus Christ of Latter Day Saints claims Emack entered the plea because he doubted he could get a fair trial in the small West Texas county where jurors have reliably convicted sect members since the raid on the Yearning for Zion ranch.

Both sides are scheduled to give oral arguments Wednesday before the 3rd District Court of Appeals, where Emack’s attorneys are expected to rip into the search warrant obtained by Texas authorities. The FLDS church has long claimed the raid was invalid because it was triggered by phone calls that turned out to be a hoax.

The calls to a domestic abuse hotline claimed to be from a 16-year-old mother being abused on the ranch in Eldorado. Authorities later learned the girl didn’t exist.

“The six-day siege of the YFZ Ranch community in April of 2008 was a law enforcement debacle of unprecedented scope and magnitude,” wrote Gerald Goldstein, Emack’s attorney, in a 49-page brief filed with the court.

The appellate court isn’t expected to make an immediate ruling.

State prosecutors responded in court filings that the trial judge in Schleicher County already denied earlier attempts to suppress evidence from more than 900 boxes and 66 computers seized at the ranch. They also described Emack as paranoid that state officials targeted his church solely because of the members’ religious beliefs.

“(Emack) plainly sees evidence of his persecution in everything; in every act of every state actor involved in his ultimate arrest and prosecution, at every stage,” prosecutors wrote.

Emack had a child with the teenage girl after the church wed them in a “spiritual” marriage, according to prosecutors. His attorneys allege state District Judge Barbara Walther made 21 errors in failing to uphold their motion to suppress evidence collected from the raid.

More than 400 children living at the sprawling ranch were swept into temporary state custody during the raid. Twelve members of the church, including sect leader Warren Jeffs, went on to face charges of bigamy, sexual assault or both.

Seven of Jeffs’ followers have been prosecuted since last year, and all have been convicted. Only in one case have jurors deliberated more than two hours.

Jeffs was extradited to Texas last year but appears unlikely to stand trial anytime soon on charges of bigamy and sexual assault. He has appeared in court with four different attorneys, had his trial date pushed back twice, and the court has yet to rule on substantial motions such as where the trial will even take place.

The FLDS church is a breakaway sect of the Church of Jesus Christ of Latter-day Saints, the Mormon church, which renounced polygamy more than a century ago.

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