The leaders sinned

Here is an example of a straw man fallacy:

"If the ones called to leadership sinned, then there is no God", 

or 

"If the ones called to leadership sinned then it isnt Gods church"

I will try to explain this briefly.

The model of the universe which makes sense to me is one in which MAXIMUM agency is permitted to allow for MAXIMUM growth and opportunities for learning. (Abraham 3)

God calls people who are willing to do the work.(D&C section 4)

He does not call people that he knows won’t make any mistakes. (Read entire bible for examples)

When God calls someone (because they are willing to do a work), He does not suddenly remove their free agency, remove their temptations, or make it impossible for them to do bad things.

The people that God calls have a stewardship and responsibility (or charge) to be a good person and do a good job at what they are called to do. (Matthew 21)

If they do a good job and are a good person, they receive of greater joy in this life and in the next. (Matthew 25)

If they do a bad job and are a bad person, they receive of less joy in this life and in the next. (Jacob 1:19)

At any point a person who has done bad things can choose to change and do good things, just as a person who does good things can change and do bad things. (Hebrews 8)

The point of this life is to learn and gain experiences that are only available in a mortal environment with agency of choice. This can happen whether you are a member of the church or not, or whether you do bad things or not.

The church is only Christs Church inasmuch as the members are Christs hands, his mouth, his feet. When they fail to be these things, the Spirit of the Lord is removed and the church fails to be Christs until the people repent.

This has happened MANY times throughout history. It happened in the days of Moses on multiple occasions, it happened in the days of Jesus. It happened in the Book of Mormon on multiple occasions (see “pride cycle”) and it happens in modern days too. That is why people are removed from their callings, and that is why who whole church is proclaimed to be under condemnation (God does not approve of them) (D&C section 84)

If you imagine that the church isn’t going through the pride cycle, it might be good to realize that neither did the Jews when they crucified Christ. The church members (leaders are members too) are fallible, imperfect and need to repent in order to do a good job in their stewardship.