The 1890 Manifesto was issued saying the LDS Church no longer practiced polygamy.  However, it was practiced secretly.  LDS Apostle Reed Smoot was elected as a US Senator from Utah in 1902, causing Congress to investigate whether the LDS Church had continued to practice polygamy.  Lindsay Hansen Park, host of the Year of Polygamy podcast, will give us more details into early 20th century practices and we will talk more about the apostle/senator Reed Smoot.

Lindsay:  Reed Smoot was a Mormon senator, of course, because he was the representative from Utah.
GT:  He was an apostle also.
Lindsay:  He was an apostle, and he was basically the scapegoat. He took a lot of heat for Mormon polygamy, because he’s over in Washington D.C., just trying to do what he does.
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GT: Reed Smoot was elected as Utah senator. Even though Reed was an apostle, he was also a monogamist. But Congress refused to seat him. So we have these Reed Smoot hearings that lasted for like two years.
Lindsay:  Yeah, In the Reed Smoot hearings–so basically, he is brought in front of the government.  They ask him all kinds of questions. They ask him all kinds of questions about Mormonism, Mormon theology.  Actually, if you read the transcripts, it’s fascinating look at Mormon theology.
GT:  They go through the temple ceremony as well.  It’s in the Congressional Record.
Lindsay:  They do and they asked him all kinds of questions about polygamy. He is forced to answer. I think he answers dishonestly, sometimes, but again, you’re looking at this idea of, we have…
GT:  But it’s not just Reed because they pulled in the prophet who by then I’m not sure. Was that…
Lindsay:  So Joseph F. Smith was forced to [testify.]
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Lindsay:  This is still at the time when we’re not sure if Mormons are allowed to vote, or if they are even considered citizens of the United States, or if they have the rights of United States citizens. So when Reed Smoot is elected, it’s about a four year struggle where people are saying, “Does he even get to do this? Is he even legitimate?  Does he need to be here?”
One of the things that they focused on in his hearings were Mormon oaths. We talked about the temple ceremony earlier, but there were oaths in the temple, [such as] the oath of vengeance that fundamentalists still adhere to. Basically [they] have to promise that they would avenge the murder of Joseph Smith, until the third and fourth generation. After Joseph Smith was killed, this was added into the temple, where there was this oath that you would take where you would avenge the deaths of the Prophet from those who had murdered him. [This] is you know why Mountain Meadows Massacre and all these other things are justified under these oaths that ends justify the means and we can do anything outsiders.  So the federal government was like, “Why are we going to let Mormons in when we’ve heard for years about these oaths.  You want to kill us.”  What should we do? Polygamy becomes the battering ram for that. So they’re in this conflict.
Joseph F. Smith is the prophet now at the time. He encourages Reed Smoot in these hearings.  This is why I brought up Joseph F. Smith because the important thing that you have to understand is Joseph Smith, III is Joseph Smith, Jr.’s son. Emma Smith rejects polygamy. Her church stays in Nauvoo, the RLDS [Church]. She believes her son, Joseph, III, has the most credentials to take on the church. There’s a good argument for that case. So she backs him. All the saints come West who are practicing polygamy in the Brighamite tradition. You have Joseph F. Smith and his cousin, Joseph Smith, III.  Hyrum’s son [leads the LDS Church],