I have just been re-elected President of our small nonprofit animal protection organization after three years off the board. We have been trying to sell some real estate since we inherited it in 2002. My choices of a board member capable of heading the Property Committee to sell this property were zero. I appointed myself head of the committee knowing I would take flack from a non-board member who makes trouble as a hobby. As President, can I appoint myself if I think I am the best person for the position?
This is a question for your bylaws. Normally, a board appoints members of all of its committees, but many bylaws say that appointments will be made by the President, normally with the approval of the board. It would be very rare that the President would be specifically kept off a committee (other than the nominating committee, perhaps), and many bylaws make the President an ex officio member of all committees. Who appoints the chair of a committee is also an open question. Committees often elect their own chairs, but bylaws sometimes give that power to the President, also subject to approval of the board. If there is a serious question about your self-appointment as chair, I would ask the board to ratify the choice.
For more information on bylaws, consider our webinar; Bylaws: The "Constitution" of Nonprofits - The Art and Science of Making Them Work.