Jerald and Sandra Tanner

The Tanners founded the Utah Lighthouse Ministry (UTLM), whose stated mission is "to document problems with the claims of Mormonism and compare LDS doctrines with Christianity".

They met in the spring of 1959, in Salt Lake City, at a religious meeting of Pauline Hancock's Church of Christ (Lukeite),[3][4] Soon after they were introduced, Jerald and Sandra began jointly researching the subject of Mormonism.

After 47 years of marriage, Jerald died in Salt Lake City on October 1, 2006, as a result of complications arising from Alzheimer's disease.

[5] The Salt Lake City Messenger was a biannual newsletter they published from 1964 to 2022 containing copies of primary documents and discussion critical of LDS history.

First of all, from paleographic and historical considerations, the Book of Breathings papyrus can reliably be dated to around A.D. 60–much too late for Abraham to have written it.

The Tanners have also published photo-mechanical reproductions of texts such as complete sets of early-LDS periodicals, including Messenger and Advocate, Times and Seasons, and the Millennial Star.

Their version contains the margin notes made by Elder B. H. Roberts, who compared this text with the Book of Mormon at the request of an LDS leader.

[10] The Tanners question the character and integrity of the witnesses to the Book of Mormon; they discuss the different accounts that Joseph Smith gave of the First Vision.

[11] Lawrence Foster, a non-Mormon historian of Mormon history, has offered a mixed assessment of the Tanners and their work.

On the negative side, Foster has written that, until the Tanners "are prepared to abide by accepted standards of scholarly behavior and common courtesy, they can expect little sympathy from serious historians.

"[12] He criticized them for "a holier-than-thou stance, refusing to be fair in applying the same debate standard of absolute rectitude that they demand of Mormonism to their own actions, writings, and beliefs… The Tanners seem to be playing a skillful shell game in which the premises for judgment are conveniently shifted so that the conclusion is always the same—negative.

For instance, the historian Daniel C. Peterson, the former chairman of Foundation for Ancient Research and Mormon Studies (FARMS) at Brigham Young University, suggested the Tanners' willingness to debunk false documents, regardless of their content, was a sign of integrity: There are some anti-Mormons out there that I hold in contempt.

He even went as far as to publish an attack on the Salamander Letter, shocking many scholars, historians, and students who believed the document was genuine.