Parley P. Pratt says that fornicators have forfeited their right to life based on Paul's teachings in 1 Corintians 5:5.
"Marriage and Morals in Utah," Deseret News 5, no. 45 (January 16, 1856): 357
Again:—1st Corinthians—chapt 5th, verse 5th. The Apostle Paul, in reference to a person in the church who had committed fornication, exhorted the saints:—"to deliver such a one unto Satan for the destruction of the flesh, that the spirit may be saved in the day of the Lord Jesus."
This destruction of the flesh must have had reference to the death of the body; the man having justly forfeited his life in accordance with the law of God. And the spirit being saved in the day of the Lord Jesus, must have had an allusion to the great day of his second coming: thus showing that the fornicator, under the light of the gospel, had forfeited his life in this world, and his salvation in the world to come, for at least eighteen hundred years.