The Case-Zablocki Act of 1972 requires the President to notify the Senate within 60 days of an executive agreement. The president`s powers to conclude such agreements have not been restricted. The reporting requirement allowed Congress to vote in favor of repealing an executive agreement or to refuse funding for its implementation.   Most executive agreements were concluded on the basis of a contract or deed by Congress. However, presidents have sometimes reached executive agreements to achieve goals that would not find the support of two-thirds of the Senate. For example, after the outbreak of World War II, but before the Americans entered the conflict, President Franklin D. Roosevelt negotiated an executive agreement that gave the United Kingdom 50 obsolete destroyers in exchange for 99-year leases on some British naval bases in the Atlantic. 70 This procedure is correct, with the exception of a few exceptions that are caused by peculiarities in the publication process. For example, the guide (2011) lists the START-I agreement as being indexed in TIF (2010) and not in TIF (2011), although the agreement expired on December 5, 2009 (The corresponding identifier is KAV 3172, see the State Sub-Department, A Guide to the United States Treaty in Force 870 (Igor I. Kavass ed., 2011).) This is because the contract expired too shortly before the 2010 TIF publication deadline.
However, all agreements are also concerned with the specifics of the underlying publication mechanism, making it unlikely that these errors would distort the estimate. Domestically, the issue of legal substitutability has traditionally been more controversial. Of course, there is little argument that congressional participation can be completely suppressed by replacing the treaty with the single executive agreement. However, views on the interchangeability of contracts and agreements between Congress and the executive branch are less harmonious at the bottom of page 29. The Constitution does not explicitly mention the existence of an instrument similar to the executive agreement of today`s Congress, which gives rise to a debate on how to interpret that silence. For early proponents, it was more than enough to show that interchangeability offers flexibility and best describes the practice of American foreign policy to assert that treaties and executive agreements in Congress should serve as legal substitutes. Footnote 30 The later arguments were based on the idea of the existence of “constitutional moments” that would inform constitutional interpretation through the consistent practice of the President, Congress and the Supreme Court. Footnote 31 Such moments, which were created primarily by practice in the 1940s, would have changed the importance of the contractual clause, which was a constitutional basis for the executive agreement of Congress. Table 1 presents summary statistics.
As can be seen, 5% of all agreements were concluded between 1982 and 2012 in the form of a treaty, which characterizes the use of the treaty. 20% of all agreements were cancelled during the observation period. The average agreement was valid for 15.26 years. Of the agreements that are no longer in force, the average shelf life is 7.3 years. The LPPC values are between 17 and 17, with an average value of 0.10 euros. On average, 50 per cent of Senate seats were held by the presidential party at the time the agreement was signed. In 71 percent of the agreements, the government was divided, with the White House held by one party, the Senate, the House of Representatives or both by the other. Taken together, these figures indicate that the average agreement could not have been adopted in the form of a treaty without multi-party support, making the treaty a potentially costly instrument.
44 108 AJIL Unbound (2014), available from www.cambridge.org/core/journals/american-journal-of-international-law/ajil-unbound; See also Bradley, note 9 above, at 85 (accept with Hathaway that the different use of contracts and executive agreements does not reflect a recognizable logic).