Constitutional Proposals Part IV: Proportional Representaion in the House

Dahl takes issue with what he calls the “American hybrid,” that is, a constitution which is neither strongly majoritarian (by virtue of multiple majorities in a system of checks and balances) and yet has little consensual or proportional aspects to it; in fact, it “may possess the advantages of neither and the defects of both” types of systems (115). With regards to the first charge about the weakness of American majoritarianism, I am inclined to disagree with Dahl. I believe the American system of checks and balances as laid out in our present constitution is both democratic and practical, and Dahl himself admits that “the evidence is mixed” regarding the efficiency or inefficiency of such a system (111). With regards to the second charge about a lack of proportionality under our present constitution, I must agree that the single district, winner-take-all method of election, most notably in the U.S. House of Representatives, is neither very fair nor democratic. To rectify this problem, I would support the implementation of a system which combines proportional representation with single member districts, as suggested by Dahl.
The reason for such a combination is rooted in the idea that the elected members of the House are representatives, that they are inclined to more or less act on the behalf of the citizens back in their district who elected them. This is something of a hallmark of American government, as I believe it should be. A proportional system, for all its advantages of political equality, greatly reduces the level of regionally specific representation. For these reasons, a combination of the two may be most appropriate for our federal nation. In such a system, half of the seats in the House would be occupied by members elected by majorities in single-member districts, thus satisfying the representative aspect. The other half of the seats would be filled by party nominees, based proportionally upon the voting results from the election, ensuring that minority voters would be fairly represented in the House even if they lost in the single-member district elections, and thus satisfying the political equality aspect.
It should be noted that a criticism of proportional representation is that it is impractical and inefficient for a society which lacks a strong common culture, whether ethnic, religious, geographic, etc. I believe this is a fair criticism, and in a nation such as the U.S. is worthy of consideration. However, I also believe that a critic could logically predict that a two-party system, such as we now possess, is apt to strong discontent and eventual upheaval. And yet, American politicians for over two centuries have maintained a strong government under a two-party system. They have done this by forming coalitions within their own parties and with members of the opposition, and by the successful utilization of compromise, that vital element of any democracy. For this reason, I believe that a proportional system could be made to work in the U.S., for though Americans do indeed lack a common ethnic, religious, and geographic heritage, we possess a great political heritage.
A final note on proportional representation: given the very real possibility of single-issue or radical parties preventing efficiency in the legislature (another justified criticism), there should be a minimum threshold above which a party must rise in order to seat a candidate. For the sake of efficiency and as a bulwark against minority radicalism, I would propose that this threshold be set rather high, at a minimum of 5%, at least.