According to John Tvedtnes, anyone can make a promise to return to a particular subject and give further details, but if Joseph Smith would have been making up the Book of Mormon narrative as he went along in dictation (which he dictated only once through to Oliver Cowdery) it would have been difficult for Joseph Smith to fulfill all such promises. As an abridger of the Nephite records, Mormon makes several important promises which are later fulfilled. One example is found in Helaman 2:12-14. Here Mormon promised to speak more of Gadianton and his band "hereafter." The problems caused by the "robbers" are detailed in Helaman 6; 3 Nephi 1:27-29; 2:11-18; 3:1-4: 29; 4 Nephi 1:42-44; Mormon 1:18.
Mormon's comments in Helaman 2:12-14 are particularly interesting, for they show how the historian worked. In verse 13, he wrote, "And behold in the end of this book ye shall see that this Gadianton did prove the overthrow, yea, almost the entire destruction of the people of Nephi." He clarified what he meant by adding, "Behold I do not mean the end of the book of Helaman, but I mean the end of the book of Nephi, from which I have taken all the account which I have written."
Mormon's meaning is uncertain. Perhaps he had reference to the large plates of Nephi, kept by Helaman and other Nephite scribes. However, at no other time are the large plates called the "book" of Nephi (see 4 Nephi 1:21).
In Helaman 2, we read of the "secret acts of murder and of robbery" (verse 4). If the history recorded in this chapter was really a "secret plan" (verse 8), how is it that it was so readily known that there even existed a secret society? That there were murderers could not be doubted, for the crimes had indeed been committed. But contemporary Nephites could have known nothing of the secret pacts until, at some future time, there should be a confession or other evidence. The discovery of the Gadianton band is related beginning in Helaman 6, where we read of the arrest of some of the robbers.
As noted in Helaman 3:37, "Helaman died, and his eldest son Nephi began to reign in his stead." If Helaman 6 comprises part of the record made by Nephi, son of Helaman, than it could be from the book of this Nephi that Mormon took his information for the account of the "secret band" in Helaman 2. As an historian, he had access to documents post-dating the events themselves, documents that could elucidate the hitherto unknown aspects of those historical events. No doubt Helaman's record made mention of the murders, but without knowing about the organization of the Gadianton band. This information being supplied by documents written at a latter time, was added in its proper historical sequence by Mormon, during the abridgement process.
It may be, however, that Helaman 6 is part of the record kept not by Nephi, but by his brother Lehi, as suggested by Sidney Sperry. If so, then the "book of Nephi" to which Mormon referred is perhaps the one known to us as 3 Nephi, where we also read much about the secret band. [John A. Tvedtnes, "Mormon As an Abridger of Ancient Records," in The Most Correct Book, pp. 10-11]
Note* I find the correlation to the entire record of the large plates as the "book of Nephi" much more plausible. If Mormon declares that he had "taken ALL the account which I have written" from "the book of Nephi," then I would think he was referring to the large plates of Nephi. Besides, Helaman 3:37 gives substance to the idea that Nephi, the son of Helaman took over as record keeper of the large plates upon his father's death. [Alan C. Miner, Personal Notes]
“This Gadianton Did Prove the Overthrow”
Who Are the Gadiantons Today?
According to Cleon Skousen, since the Book of Mormon prophets warn us that the same type of conspiracy would exist in our own day (see 2 Nephi 26:20-22), let us briefly summarize the characteristics of this movement and the criminal tactics which it employed.
1. It often turned out that their leaders rose to power by murdering their former friends and associates (Ether 8:13-17; 9:4-12).
2. The leaders made flattering promises to any who would join in the subversive conspiracy which was designed to use criminal tactics in acquiring wealth and then seizing control of the government (Helaman 2:5; Ether 8:17)
3. They did not come out in the open and allow the people to know of their intentions or tactics, but operated as an illegal, underground apparatus (Helaman 6:21-22).
4. They had their own secret code of discipline and their own secret police to bring in dissenters or defectors for punishment (Helaman 6:24) The penalty for revealing their secrets was death (Moses 5:50).
5. They demanded all their "rights" under the Constitution until they came into power, then they destroyed the liberties of the people and claimed "rights" exclusively for themselves (Helaman 7:4; 3 Nephi 6:30; 7:6).
6. As soon as they came into power they discharged those who occupied key positions and appointed their own hard-core members to all positions of trust (Helaman 7:4).
7. All who tried to defend the Constitution and preserve traditional order and justice were prosecuted as though they were the offenders (Helaman 7:5).
8. However, the leaders ignored or deliberately covered up the crimes of their own members (Helaman 7:5)
9. They created a privileged, bureaucratic class of criminal aristocrats to govern the people (Helaman 7:5).
10. They radically altered the provisions of the law so they could claim to be operating "legally" (3 Nephi 7:6).
11. They employed propaganda to obscure the weaknesses of their own administration and used the voice of prominent people to spread their propaganda line (Helaman 8:1, 7-8).
12. They waged continuous ideological warfare to break down the moral and political independence of the people. As part of this campaign they killed religious leaders (3 Nephi 7:6-7).
13. Then they turned the whole society toward moral debauchery similar to their own profligate lives (Helaman 6:23; Ether 8:16).
14. They tried to replace revealed religion by encouraging the people to practice primitive, heathen rites with emphasis on the collection of gold and silver to contribute to their idolatrous priestcraft (Helaman 6:31).
15. They would not tolerate any kind of resistance or public discussion of the issues. They called their own kind of criminal dictatorship the only "good" government and demanded that every citizen support them or be exterminated (3 Nephi 3:7-8).
16. In attacking the legitimate government and seeking to overthrow it they claimed they were waging war to recover "their" rights and restore "their" government which had been wrongfully taken away from them (3 Nephi 3:10).
17. They used Communist-type peace propaganda, claiming they did not want war. They merely wanted their opposition to accept the inevitable and surrender "peacefully" (3 Nephi 3:4-7).
18. They promised that if the opposition would surrender, its people would not be placed in slavery but would become partners and brethren in the great new order. They neglected to mention that under their police state all their partners and brethren were subject to the most rigorous death-penalty oaths, and were therefore under a system of criminal slavery (3 Nephi 3:7).
19. Their administrations were always characterized by assassinations, immorality and revolution. They waged total war of such wholesale proportions that established government broke down completely and entire kingdoms were literally wiped out (Ether 9:11-12; 11:6-7).
20. If the people did succeed in overthrowing the Gadianton movement and burying their secret oaths and plans of operations, Satan revealed them to the next generation and the whole terrible cycle began all over again (Alma 37:29,32; Helaman 6:26-27).
[W. Cleon Skousen, Treasures from the Book of Mormon, Vol. 3, pp. 3271-3272]