This is a category for official U.S. government; i.e., commissions, councils, conferences, etc., which are convened in a conference format or investigative format.
This category can also be for committees of the legislative branch, meaning the US Senate or House of Representatives, for those committees which serve in a special investigative, inquiry, or review function.
Please note that U.S. federal commissions which serve as ongoing agencies would actually belong in another category, such as: Category:Agencies of the United States government, or Category:United States federal boards, commissions, and committees, or Category:Independent agencies of the United States government.