Center for the Study of Democracy

This paper tests the commonly held belief that the extremely proportional electoral system used in Israel gives disproportionate influence to small parties. This hypothesis is tested using power score analysis of the bargaining power of small parties in the Israeli Knesset (Penrose 1946, Banzhaf 1965), and also by considering the degree to which small parties have been able to win a disproportionate number of cabinet portfolios. Considering the period 1977-2003, we find that small parties only have disproportionate bargaining power in three Knessets in the 1980s, and in only one of these were they able to obtain more cabinet seats than their size would predict. Small parties only have disproportionate bargaining power in elections where the two large parties are essentially tied. Given that this situation will produce a hung parliament and give small parties the balance of power in most electoral systems (including single-member district plurality), we should be very careful about generalizing from the Israeli case to the performance of proportional electoral systems overall.