Oliver Cowdery was excommunicated in part:

“For seeking to destroy the character of President Joseph Smith, Jun., by falsely insinuating that he was guilty of adultery [with Fanny Alger].”

^{Seymour Brunson, History of the Church of Jesus Christ of Latter-day Saints – Volume 3 (Salt Lake City, UT: Deseret News, 1905 edition. Instance dated 7-11 April 1838), 16.}