SALT LAKE CITY - The convictions of polygamist leader Warren Jeffs were reversed on Tuesday by the Utah Supreme Court, which ordered a new trial and said a jury received incorrect instructions before considering his role in the 2001 nuptials of a 14-year-old girl to her 19-year-old cousin.

Jeffs, 54, was convicted in 2007 of two counts of first-degree felony rape as an accomplice. He is serving two consecutive terms of five years to life in the Utah State Prison.

A telephone call seeking comment from the Washington County attorney's office and the Utah attorney was not immediately returned Tuesday. Jeffs' lawyers scheduled a news conference later Tuesday.

Jeffs is head of the Fundamentalist Church of Jesus Christ of Latter Day Saints. The group, based on the Utah-Arizona state line, practices polygamy in marriages arranged by church leaders.

Jeffs performed the religious marriage of Elissa Wall and Allen Steed in a Nevada motel and later counselled Wall to be obedient and give her "mind, body and soul" to her husband in an effort to make an unhappy marriage work.

During the trial and later in her book, "Stolen Innocence," Wall said she objected to the marriage and was forced into sexual relations with her husband.

The Associated Press does not typically name victims of alleged sexual assault, but Wall has frequently spoken publicly about the case.

In its ruling Tuesday, the court agreed with defence attorneys who argued that jurors should not have been told to decide whether Wall's marital relations were consensual based on Jeffs' actions and his role as her religious leader. That essentially equates Jeffs with Steed -- the person who allegedly has had nonconsensual sex.

Justices said prosecutors were wrong to make that leap.