Joseph Smith claims that after he translated the plates, he returned them to the angel Moroni. Therefore, there is no way to verify the veracity of the plates or Smith's translation. Smith's only defense of his account is the eleven men who signed statements claiming to have seen the golden plates. Therefore, the credibility of Smith's account rests on the testimony of these eleven witnesses. There are three key witnesses who claim to have seen the angel show the golden plates to them. The remaining eight allege to have seen the plates but not the angel. The LDS church asserts these men never denied their testimony. However, when we examine the lives of the witnesses, we find they were untrustworthy, wavering, and gullible witnesses.
Six of the eleven witnesses, including the three key witnesses were eventually excommunicated from the church. Former Mormon President Ezra Taft Benson summed up the legacy of the eleven witnesses this way. "Six of the original Twelve Apostles selected by Joseph Smith were excommunicated. The three Witnesses to the Book of Mormon left the church. Three of Joseph Smith's counselors fell--one even helped plot his death. . . . The wolves among our flock are more numerous and devious today than when President Clark made a similar statement [in 1949]."{6}
Let us first examine the character of the three key witnesses since their testimony is the most important. In a letter dated December 16, 1838, Joseph Smith stated this about the three key witnesses and John Whitmer, one of the eight. "John Whitmer, David Whitmer, Oliver Cowdery, and Martin Harris are too mean to mention."{7}
Martin Harris' testimony shows him to be a gullible and unstable man. He changed his religious conviction approximately thirteen times. He had joined several Christian denominations and other cult groups that include the Universalists, Strangites, and the Shakers. {8}(Ankerberg, 196) In Doctrine and Covenants, Joseph Smith gave revelations in which he denounces Martin Harris and calls him a "wicked man."{9} The Mormon leaders published an article in the Elder's Journal, a Mormon publication edited by Joseph Smith, in which they accused Harris guilty of "swearing, lying, cheating, swindling, drinking, with every species of debauchery. . ." (Elders Journal, August, 1838, 59).{10} Here the leaders of the Mormon Church strongly criticize the character of Harris.
Oliver Cowdery was also shown to be a very gullible man. He was led astray by Hiram Page, one of the eight witnesses who himself claimed to have divine revelations from his own seer stone. Although Joseph Smith denounced Hiram as a false teacher, Smith stated "to our grief, however, we soon found that Satan had been lying in wait to deceive. . . . Brother Hiram Page had in his possession a certain stone, by which he obtained certain 'revelations' . . . all of which were entirely at variance with the order of God's House, . . ."{11} Despite Smith's condemnation, Oliver Cowdery joined Page's movement. Not only was he a gullible man, he was also indicted on several accounts of fraudulent business practices. The Mormon Church in a letter wrote, "During the career of Oliver Cowdery and David Whitmer's bogus money business, it got abroad into the world that they were engaged in it. . . . We have evidence of a very strong character that you are at this very time engaged with a gang of counterfeiters, coiners, and blacklegs . . ."{12} Cowdery was eventually excommunicated and he later joined the Methodist Church.
David Whitmer wrote, "God spake to me again by his own voice from the heavens, and told me to 'separate myself from among the Latter- day Saints, for as they sought to do unto me, so should it be done unto them." In the spring of 1838, the heads of the church and many of the members had gone deep into error and blindness. . . . About the same time that I came out, the Spirit of God moved upon quite a number of the brethren who came out, with their families, all of the eight witnesses who were then living (except the three Smiths) came out; . . ."{13} Here David Whitmer denounced the Mormon Church and encouraged people to follow his example and the example of the other witnesses and leave the church.
Joseph Smith in response attacked the character of David Whitmer. Smith stated, "God suffered such kind of beings to afflict Job . . . this poor man who professes to be much of a prophet, has no other dumb ass to ride but David Whitmer, to forbid his madness when he goes up to curse Israel: and this ass not being of the same kind as Balaam's . . . he brays out cursing instead of blessings. Poor ass!"{14}
The character and life of the eleven witnesses to the Book of Mormon are very different from the Apostles of Christ. None of the Apostles wavered in their defense of Christ, even though all suffered and most died for their faith. The Apostles remained consistent in their teaching and never fell into any type of apostasy. Their lives were marked by honesty and integrity. They were never indicted for any criminal activity except for preaching Christ. The character of the Book of Mormon's eleven witnesses does not strengthen Smith's defense but cast further doubt on its authenticity.
Probe Ministry website quote
Each of these three witnesses throughout their lives stood fast in their testimony of seeing the plates, seeing the angel and hearing the voice of God commanding them to bear testimony of what they saw.
Some more information about these witnesses and their testimonies:
http://bookofmormonfacts.com/book-of-mormon/mouth-two-three-witnesses/