Checks and Balances: The Legislature has power over the Executive to amend, delay or reject legislative proposals, override vetos, power of the purse and to declare war (last used in 1941 for Pearl Harbour). The Senate can refuse to approve executive appointments or ratify treaties and the House can call for investigations, e.g. the 2012 Benghzi attacks on U.S. govt. facilities in Libya by ansar al-sharia. The House can also impeach presidents, e.g. Bill Clinton was impeached in 1998 for a supposed sexual relationship with Monica Lewinsky but was aquitted and remained in office.