Institutional Reform and Trade Liberalization 675 direction.22 The vote on the RTAA in 1934 was just as partisan as the vote on Smoot- Hawley,with the Republicans sticking to their historical platform favoring high tar- iffs:Republicans voted 111-12 and 30-5 against the bill in the House and Senate, respectively,whereas Democrats voted 279-4 and 51-7 for the bill.Clearly,with a few more Republican legislators around to cast votes in 1934 or 1937,and a few less Democrats,the historic reform would have been quickly scuttled.Table 1 shows the votes on legislation extending the president's authority to negotiate trade agreements between 1937 and 1974.23 It seems clear that there was no general shift away from protectionism and in favor of liberalizing delegation in the years immediately following the 1930 debacle,as the simple learning thesis would imply,but rather a far more gradual evolution of party positions in which both became more internally divided on the matter.24(I will return to this point later in the article.) The Lohmann-O'Halloran model can do little better than the cruder form of the anti-logrolling argument on this score.It does anticipate that some level of partisan- ship in presidential tariff setting(a parameter)can result in partisan voting contests over delegation,as occurred in the 1934 RTAA vote and votes on extensions of negotiating authority in the 1930s and 1940s.But votes extending the president's authority over trade policy have grown increasingly less partisan over time as signifi- cant divisions have appeared in each party on the issue.The Lohmann-O'Halloran model cannot account for this trend because it demands that all members of the same party cast identical votes when it comes to delegation.The model also contains no theory of presidential partisanship in tariff-setting,it should be noted,and allows for no other source of congressional partisanship on the trade issue:a remarkable oversight given the historical conflict between Democrats and Republicans over the tariff. The overall evidence for the Lohmann-O'Halloran model from just the post-1934 record of delegation and policy change is far from convincing.True,there are several examples that seem to fit with their prediction that greater delegation should be associated with unified governments than with divided ones:the Republican Con- gresses of the late 1940s shortened the period of delegation to the Democratic presi- dent (Truman),for instance,and imposed "peril point"provisions that prohibited tariff reductions that threatened "serious injury"to domestic industries.In 1974 a Democratic Congress imposed a new congressional veto on trade agreements negoti- ated by the Republican president (Nixon).But there are also counter-examples:in 1951,for instance,a Democratic Congress revived the peril-point constraint and imposed it on their own president.In 1953 and 1954 Republican Congresses required an enormous amount of arm twisting before they were willing to grant the Eisen- hower administration a renewal of bargaining authority and refused to extend it for 22.Schneitz1994,128-32. 23.Appendix I provides a longer list of votes on trade legislation between 1890 and 1994,including bills after 1974 that,while granting new extensions of authority to the president,included a host of other measures 24.See Watson 1956:and Hiscox 1997.Institutional Reform and Trade Liberalization 675 direction.22 The vote on the RTAA in 1934 was just as partisan as the vote on Smoot￾Hawley, with the Republicans sticking to their historical platform favoring high tar￾iffs: Republicans voted 111-12 and 30-5 against the bill in the House and Senate, respectively, whereas Democrats voted 2794 and 51-7 for the bill. Clearly, with a few more Republican legislators around to cast votes in 1934 or 1937, and a few less Democrats, the historic reform would have been quickly scuttled. Table 1 shows the votes on legislation extending the president's authority to negotiate trade agreements between 1937 and 1974.23 It seems clear that there was no general shift away from protectionism and in favor of liberalizing delegation in the years immediately following the 1930 debacle, as the simple learning thesis would imply, but rather a far more gradual evolution of party positions in which both became'more internally divided on the matter.24 (I will return to this point later in the article.) The Lohmann-O'Halloran model can do little better than the cruder form of the anti-logrolling argument on this score. It does anticipate that some level of partisan￾ship in presidential tariff setting (a parameter) can result in partisan voting contests over delegation, as occurred in the 1934 RTAA vote and votes on extensions of negotiating authority in the 1930s and 1940s. But votes extending the president's authority over trade policy have grown increasingly less partisan over time as signifi￾cant divisions have appeared in each party on the issue. The Lohmann-O'Halloran model cannot account for this trend because it demands that all members of the same party cast identical votes when it comes to delegation. The model also contains no theory of presidential partisanship in tariff-setting, it should be noted, and ,allows for no other source of congressional partisanship on the trade issue: a remarkable oversight given the historical conflict between Democrats and Republicans over the tariff. The overall evidence for the Lohmann-O'Halloran model from just the post-1934 record of delegation and policy change is far from convincing. True, there are several examples that seem to fit with their prediction that greater delegation should be associated with unified governments than with divided ones: the Republican Con￾gresses of the late 1940s shortened the period of delegation to the Democratic presi￾dent (Truman), for instance, and imposed "peril point" provisions that prohibited tariff reductions that threatened "serious injury" to domestic industries. In 1974 a Democratic Congress imposed a new congressional veto on trade agreements negoti￾ated by the Republican president (Nixon). But there are also counter-examples: in 1951, for instance, a Democratic Congress revived the peril-point constraint and imposed it on their own president. In 1953 and 1954 Republican Congresses required an enormous amount of arm twisting before they were willing to grant the Eisen￾hower administration a renewal of bargaining authority and refused to extend it for 22. Schneitz 1994, 128-32. 23. Appendix I provides a longer list of votes on trade legislation between 1890 and 1994, including bills after 1974 that, while granting new extensions of authority to the president, included a host of other measures. 24. See Watson 1956; and Hiscox 1997