The church (LDS) has taught members to believe that church-approved materials were the most trustworthy source of information about the church. The Church also warns that anti-Mormon literature is full of half-truths, lies, and statements taken out of context.
Mormons are taught to use the label "anti-Mormon" to refer to anyone or anything critical of the church. The phrase "anti-Mormon" is one of the most powerful tools for controlling the information members receive. Once members learn to discount ANYTHING that's critical of the church, they self monitor what they read.