Helaman 2:2 Helaman...was appointed to fill the judgment-seat
Helaman is elected to the judgment-seat only after another contention. Certainly, the loser in this election was supported by Kishkumen and company. However, Helaman prevails and will hereby consolidate his religious and political authority. It was to him whom Shiblon had committed the plates (Alma 63:11). He became the high priest over the church and the chief judge, the very combination of offices which had become so burdensome to his grandfather Alma (Alma 4:17-20). Although the judgment-seat was the most powerful political office among the Nephites, one could hardly say that it was a popular office. With the band of Kishkumen at large, the life of the chief judge was always in danger. Indeed, as soon as Helaman becomes the chief judge, the band begins to plan his death.
Helaman 2:4 Gadianton...was exceedingly expert in many words...to carry on the secret work of murder
"Gadianton was a Nephite apostate; the founder and first leader of the robber bands that bore his name. He is first mentioned in connection with the attempt by Kishkumen to assassinate Helaman, the Chief Judge, 50 B.C. At that time Gadianton had organized his band and bound its members together with the most horrible and blasphemous oaths and covenants to stand by and protect each other in all their treasons, villainies, and crimes. These oaths and secret compacts had not been searched out of the old records by Gadianton, but that same being who had revealed them to Cain, the first murderer, had whispered them to him. Gadianton was a crafty, capable man, full of strategy and cunning; a flatterer and an expert in the use of many words; and at this time he desired to be elected Chief Judge of the Nephite Commonwealth. To this ambition his followers gave full consent, as he promised them that when elected, they should fill the offices of honor and profit which would be at his disposal." (Reynolds and Sjodahl, Commentary on the Book of Mormon, vol. 5, pp. 203-4)
"Now here comes an expert, this Gadianton. He was a pro. He was the new professional Capo. Verse 4: 'For there was one Gadianton, who was exceedingly expert in many words [he was a fast talker, and that's important-they always are, you'll notice], and also in his craft.' Now this was his craft, and he was polished in it. He was proud of it. He was efficient; he did a thorough job of bumping off. He would take a contract, and he was good at it, which was 'the secret work of murder' and he could crack a bank anytime. He was good at murder and robbery. And we have experts in that today. He was a professional. He was the leader of the band of Kishkumen.
"And he worked on them and said, look if you'll put me in charge of the whole operation I can take care of my boys. If they would place him in the judgment seat-that's all he wanted-'he would grant unto those who belonged to his band that they should be placed in power and authority among the people.' (v. 5) They'd have the high office." (Teachings From the Book of Mormon, Lecture 74, p. 204)
Helaman 2:6 one of the servants of Helaman...obtained, through disguise, a knowledge of those plans
"And here's one of the servants of Helaman, '...having been out by night, and having obtained, through disguise, a knowledge of those plans...' Now what was his disguise? His disguise was that of a defector, of course. He'd come over as an insider who knew all about it, and defectors are quite common. He was a mole. He was actually an undercover man; he was a double agent for Helaman. He knew all the workings, and this is why they would come to him and why Gadianton said, lead me to him. Get me an audience with the judge so I can bump him off. So this was one of the servants of Helaman; otherwise, this looks rather confusing, but it isn't when you realize the nature of his disguise. He didn't wear a mask or a false moustache or anything like that. But his disguise was his persona. He was a [pretended] defector. He'd come over; he knew all about Helaman. And he had attained 'a knowledge of those plans which had been laid by this band to destroy Helaman.' This is their regular police practice. He was put in there as an undercover man, a double agent." (Teachings From the Book of Mormon, Lecture 74, p. 204-5)
Helaman 2:13 this Gadianton did prove...almost the entire destruction of the people of Nephi
Mormon himself later chronicles the destructive power of the Gadianton robbers. During his day, they had reached the pinnacle of their strength. But, like a parasite that kills its host, their wicked strength overcame the righteousness of the Nephites until they could no longer glut themselves upon their labors.
In the words of Mormon, 'the land was filled with robbers and with Lamanites...therefore there was blood and carnage spread throughout all the face of the land...no man could keep that which was his own, for the thieves, and the robbers, and the murderers, and the magic art, and the witchcraft which was in the land...And it is impossible for the tongue to describe, or for man to write a perfect description of the horrible scene of the blood and carnage which was among the people, both of the Nephites and of the Lamanites; and every heart was hardened, so that they delighted in the shedding of blood continually (Mormon 2:8-10; 4:11).'
"Thus we comprehend how Mormon had clearly seen from prophecy and from the social ills of his own lifetime the nature and origin of the destructive forces among the Nephites, and he knows that Satan is the ultimate source. This perspective is later echoed by his son Moroni, who laments that 'they [secret combinations] have caused the destruction of this people of whom I am now speaking [the Jaredite civilization], and also the destruction of the people of Nephi' (Ether 8:21)." (Book of Mormon Symposium Series, "Helaman - 3 Nephi 8," edited by PR Cheesman, MS Nyman, and CD Tate, Jr., 1988, p. 145)
"At this point we are assured that, in time, Gadianton's gang would prove 'almost the entire destruction of the people of Nephi' (Helaman 2:13). If ever a story was worth heeding after that announcement, this is one to which we should pay the closest attention-a nation helpless to resist the march of crime!" (The Prophetic Book of Mormon, p. 552)
Ezra Taft Benson
"Our nation will continue to degenerate unless we read and heed the words of the God of this land, Jesus Christ, and quit building up an upholding the secret combinations which the Book of Mormon tells us proved the downfall of both previous American civilizations." (A Witness and a Warning, p. 6 as taken from Latter-day Commentary on the Book of Mormon compiled by K. Douglas Bassett, p. 371)