The British Columbia Court of Appeal has ordered a new trial for James Oler, who was acquitted of taking a 15-year-old girl across the border for a sexual purpose.

The Crown appealed the verdict in the case of the former leader of the Fundamentalist Church of Jesus Christ of Latter day Saints in Bountiful, B.C., which practises polygamy.

The Crown told the appeal court the trial judge erred in concluding it had not been proven that Oler had done anything within Canada's borders to arrange the girl's transfer to the U.S.

The court also denied an appeal from Emily Blackmore, also known as Gail, who was convicted of taking a 13-year-old girl across the border for a sexual purpose.

A lawyer for Blackmore argued that she likely didn't know about her husband's plan to bring the teenage girl to the U.S. to marry an older member of the sect.

The identities of the two girls are protected by a publication ban.

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