This morning my facebook and twitter feeds were inundated with declarations by my Latter-day Saint friends decrying capital punishment and the execution of Troy Davis last night. “I want to take this opportunity to voice my outright and unequivocal opposition to the death penalty,” said one. “A sad day to be a Georgian,” lamented another. I wasn’t really surprised, but I am fascinated by how the tide of public support of capital punishment has ebbed among Mormons in my own lifetime.
In the 1970’s with the reinstatement of the death penalty in Utah (1973) and the execution of Gary Gilmore (1977), Mormons in general seemed to support secular capital punishment law. Though it was seldom overtly stated, justification of this method of punishment was related to the doctrine of blood atonement. Thus Utah’s preferred method of execution was by firing squad, rather than hanging or lethal injection. Joseph Smith himself had expressed an opposition to hanging, and stated that if he was going to make a law on judicial execution, he would support shooting, or cutting off the head; thus “spill[ing] his blood upon the ground and let[ting] the smoke thereof ascend up to God.”  Brigham Young developed these thoughts further, saying that it was possible for men to commit sins for which the blood of Christ could not atone. “And if they had their eyes open to see their true condition,” he said, “they would be perfectly willing to have their blood spilled upon the ground…” 
Much of the information we have on the idea of blood atonement among Mormons comes through the discussion of capital punishment and how it should be administered. For example, Jedediah M. Grant, counselor in the First Presidency of the Church, preached blood atonement in connection with his role in implementing capital punishment law in Utah:
“But if the Government of God on earth, and Eternal Priesthood, with the sanction of High Heaven, in the midst of all his people, has passed sentence on certain sins when they appear in a person, has not the people of God a right to carry out that part of his law as well as any other portion of it? It is their right to baptize a sinner to save him, and it is also their right to kill a sinner to save him, when he commits those crimes that can only be atoned for by shedding his blood. If the Lord God forgives sins by baptism, and . . . certain sins cannot be atoned for . . . but by the shedding of the blood of the sinner, query, whether the people of God be overreaching the mark, if they should execute the law . . . We would not kill a man, of course, unless we killed him to save him.” 
In 1891, President Wilford Woodruff explained that it was a fundamental doctrine of Mormonism that capital crime committed by an “enlightened” member of the Church could only be atoned for by the shedding of his own blood. He hastened to add that this be done “through capital punishment as practiced by the State and not the Church,” and that “the law must be executed by the lawfully appointed officer.” 
General Authority, historian and politician B.H. Roberts taught:
“But if, as seems to be the case . . . there are certain limitations to vicarious atonement, even to the vicarious atonement of the Christ then these ancient laws proclaiming that the life of the flesh is in the blood, and that ‘the blood maketh an atonement for the soul,’ make plain what is needful for the salvation of the soul where one’s sins place him beyond the reach of vicarious means of salvation—then it is the shedding of the sinners own blood that must be referred to.” 
In the 1960s capital punishment began to fall out of favor in the United States. There were no executions performed from 1967 to 1977. However, Utah opinions on the issue continued to be guided by positions of Church leaders on blood atonement. Tenth prophet and president Joseph Fielding Smith wrote,
“Man may commit certain grievous sins – according to his light and knowledge – that will place him beyond the reach of the atoning blood of Christ. If then he would be saved, he must make sacrifice of his own life to atone – so far as the power lies – for that sin, for the blood of Christ alone under certain circumstances will not avail. Joseph Smith taught that there were certain sins so grievous that man may commit, that they will place the transgressors beyond the power of the atonement of Christ. If these offenses are committed, then the blood of Christ will not cleanse them from their sins even though they repent.” 
“As far as I can see there is no difference between a firing squad, an electric chair, a gas chamber, or hanging. Death is death and I would interpret the shedding of man’s blood in legal executions as a figurative expression which means the taking of life. There seems to me to be no present significance as to whether an execution is by a firing squad or in some other way. I, of course, deleted my article on ‘hanging’ from the Second Edition of Mormon Doctrine because of the reasoning here mentioned.” 
Following Bruce R. McConkie’s reconsideration, the doctrine of Blood Atonement has not been publicly taught. Neither do Church leaders emphasize the few scriptures which pertain. Since this doctrine does not now influence the opinions of the Latter-day Saints regarding capital punishment, they have been left to form their own conclusions on the subject. From what I see, despite our foundational history, Mormon sentiment now comes down overwhelmingly in opposition to judicial execution. I’m not sure that my view is an accurate representation, and would welcome further discussion along the following lines:
First, do you agree with me that a majority of Latter-day Saints, both liberal and conservative, currently oppose the death penalty?
Second, do you agree that there has been a change since the 1970s?
Third, what factors do you think have led to this change?
 Joseph Smith, Jr., History of the Church of Jesus Christ of Latter-day Saints, 5:296 (1949)
 Brigham Young, Journal of Discourses, 4:51-54.
 Jedediah M. Grant, Deseret News, July 27, 1854, p. 2, col. 1.
 Wilford Woodruff, in a letter to the editor of Illustrated American (January 9, 1891)
 BH Roberts, Comprehensive History of the Church, 4:128,129.
 Joseph Fielding Smith, Doctrines of Salvation, 1:135,138.
 “But under certain circumstances there are some serious sins for which the cleansing of Christ does not operate, and the law of God is that men must then have their blood shed to atone for their sins. Murder, for instance, is one of these sins; hence we find the Lord commanding capital punishment.” (Bruce R. McConkie, Mormon Doctrine, p. 92)