SIDNEY RIGDON'S TESTIMONY
Sidney Rigdon, in a lengthy letter to his official paper, The Messenger and Advocate, in 1845 declared that the Prophet was responsible for the plural marriage doctrine, and said:
This system was introduced by the Smiths some time before their death, and was the thing which put them in the power of their enemies, and was the immediate cause of their death. P. 475, vol. 2.
He says he "warned Joseph Smith and his family," and told them that destruction would come upon them if they continued in their course.