Speaking of the state of mankind after the Fall, we read the following in the Book of Mormon:
For they are carnal and devilish, and the devil has power over them; yea, even that old serpent that did beguile our first parents, which was the cause of their fall; which was the cause of all mankind becoming carnal, sensual, devilish, knowing evil from good, subjecting themselves to the devil. (Mosiah 16:3)
Note how mankind is said to have become carnal, devilish, and all sorts of negative things. This flies in the face of the common but errant view among many members of the Church that the Fall produced only good and did not result in anything(s) truly negative. Furthermore, what is interesting is that this text mirrors Rom 5:19 which states that, as a result, we have become (Gk. καθιστημι) sinners and that, through justification, we become (καθιστημι) righteous (δικαιος), supporting transformative justification and refuting the historic Protestant doctrine.
For a discussion of this text and other relevant texts, see:
On the Fall and a response to the very rosy picture painted by many LDS, see the discussion under "Chapter 3: The Fall" at