Policy traps for third parties in two-party systems: the Australian case.

Despite a steady erosion of the major parties' share of the vote in Australia, minor parties have been unable to attract more than 15 per cent of the vote. Employing a variation of Katz and Mair's cartel party thesis, this paper argues that the major parties have an advantage in defining and limiting power sharing arrangements and setting and reacting to the policy agenda. They can act together to deny a third-party oxygen, or can deflect criticism of controversial policies onto the third party. A critical appraisal of seven cases of government formation involving the Australian Greens and Australian Democrats, along with two case studies of legislative negotiation shows that the electoral backlash is often borne by the minor parties. [ABSTRACT FROM PUBLISHER]