http://www.senate.gov/reference/resources/pdf/RS21308.pdfThe wording of the constitutional provision allowing recess appointments leads to a question about which positions could actually be filled that way. The question revolves around the phrase “Vacancies that may happen during the Recess of the Senate.” Does “happen” mean “happen to exist” or “happen to occur”? The first meaning would allow the President to make recess appointments to any position that becomes vacant prior to the recess and continues to be vacant during the recess, as well as positions that become vacant during the recess. The second meaning would allow recess appointments only to positions that become vacant during the recess. Although this question was a source of controversy in the early nineteenth century, Attorneys General and courts have now long supported the first, broader interpretation of the phrase.
http://congress.indiana.edu/learn_about/topic/rc_qa.php#recess_appt...
President George W. Bush has made 42 recess appointments in just over 3 years in office. President Clinton made 140 recess appointments in his two terms. The first President Bush made 77 recess appointments during his 4 year tenure. In 8 years as President, Ronald Reagan made 240 such appointments. President Carter made 68 recess appointments during his 4 years in office.
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The original purpose behind granting the President the power of recess appointments was to get around a practical problem. At the time the Constitution was written, it was expected that Congress would have short sessions and long periods of adjournment. Sessions were sometimes delayed because difficult travel conditions meant waiting a long time for enough Senators to arrive to assemble a quorum. The power given the President to make recess appointments was granted so that he wouldn?t be without top officials of government for long periods while waiting for the Senate to assemble.
Today, Congress meets for longer periods throughout the year, with shorter recesses. The motivation for recess appointments is rarely scheduling concerns any longer. Recess appointments are now more often made to circumvent the Senate confirmation process. However, Presidents have to balance the political advantages of appointing individuals the Senate has not acted upon, with the risks of alienating the Senate when it comes to future appointments.
All modern Presidents have made recess appointments both during the shorter breaks within a session of Congress as well as during the longer recess between the two sessions. Senate leaders have frequently complained about the appointments made during short intra-session recesses. Some have threatened to litigate the matter to the Supreme Court, but none have yet done that. A federal appeals court did rule in 1962 that the President had broad authority to make recess appointment decisions
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