A recent news story referred to fugitive Warren Jeffs as a “fundamentalist Mormon” and “leader of a polygamist breakaway Mormon sect.”
Polygamist groups in Utah, Arizona or Texas have nothing whatsoever to do with The Church of Jesus Christ of Latter-day Saints. To refer to them as “Mormon” is inaccurate.
Mormon is a common name for a member of The Church of Jesus Christ of Latter-day Saints. The Church discontinued polygamy more than a century ago. No members of the Church today can enter into polygamy without being excommunicated.
When referring to people or organizations that practice polygamy, terms such as those given in the first paragraph above are incorrect. The Associated Press Stylebook notes: "The term Mormon is not properly applied to the other ... churches that resulted from the split after (Joseph) Smith's death."