Hillary Clinton is set to testify in front of the House of Representatives Select Committee on Benghazi about the 2012 attack on the US consulate in the Libyan city that killed ambassador Chris Stevens and three other Americans.
It is the second time she has been called before Congress to discuss the raid by suspected Islamist militants on the US compound in Benghazi, which took place during her tenure as US secretary of state.
BBC state department correspondent Barbara Plett Usher has been following this complicated story and answered some of our readers' biggest questions about Benghazi on the BBC News Facebook page.
What does this committee do? What are the consequences for Clinton?
The committee is authorised to investigate and issue a final report on the Benghazi attacks: what hampered the government's ability to prepare for them and how it responded.
U.S. Secretary of State Hillary Clinton testifies before the House Foreign Affairs Committee about the September 11 attacks against the U.S. mission in Benghazi, Libya,Image copyrightGetty Images
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Clinton previous testified on the Benghazi attacks in 2013
As such it would be part of Congress' record on the attacks - including seven other congressional committees and a state Department investigation - which are meant to contribute to policy improvements.
But it would not have the power to punish anyone it criticises. However, depending on the conclusions there could be political consequences for Hillary Clinton, which might affect her presidential campaign
Why were we originally told US Ambassador Chris Stevens and three other Americans died because of a YouTube video that agitated a large crowd of people?


http://www.bbc.com/news/world-us-canada-34598958