Here is a clear example of a false prophet: (link). He has now twice predicted a nuclear doomsday. That his prophecies have failed to come to pass is self-evident. The just and appropriate punishment for this crime against God is death:
20But the prophet, which shall presume to speak a word in my name, which I have not commanded him to speak, or that shall speak in the name of other gods, even that prophet shall die. 21And if thou say in thine heart, How shall we know the word which the LORD hath not spoken? 22When a prophet speaketh in the name of the LORD, if the thing follow not, nor come to pass, that is the thing which the LORD hath not spoken, but the prophet hath spoken it presumptuously: thou shalt not be afraid of him.
Although Texas does not punish false prophecy with death, it does punish fraud - and should use that mechanism to punish this con artist. I have no idea whether it will.
I wonder what other mechanism than the law is available to bring this group, and particularly its false prophet to a recognition of their sin, repentance of it, and faith in Christ.
Lest you think that I am relying solely on the secular media in this regard consider this, taken from the group's own web site (here):
"By June 12, 2007 the nine-month nuclear baby will have been born, causing a third part of man to be killed over a fourth part of the earth in and around the great River Euphrates with nuclear wars."
But this man is brazen ... he now claims: "It’s plain to see that all these Prophecies of this nuclear war that will kill a third part of man over a fourth part of the earth in and around the great River Euphrates would have been fulfilled already had it not been for another Prophecy showing the Plan of Yahweh."
It should be pointed out that the Texas authorities have been after this guy on other grounds, alleging that he is a polygamist and has been violating child labor laws. Ultimately, those are unsatisfying conclusions to the matter, though perhaps it is all we can hope for.