The multi-party system the multi-party system as the title suggests, this is a MA T system where more than two parties have some impact in a state's political life Y Within Westminster the tories and the liberal Democrats provide a healthy political rivalry. Sartori wA T defines a multi-party system as one where no party can guarantee an absolute majority ot in theory, the Labour Party, regardless of its current dE parliamentary majority, could lose the next general election in britain in 2006The multi-party system The multi-party system : as the title suggests, this is a system where more than two parties have some impact in a state’s political life Within Westminster, the Tories and the Liberal Democrats provide a healthy political rivalry. Sartori defines a multi-party system as one where no party can guarantee an absolute majority In theory, the Labour Party, regardless of its current parliamentary majority, could lose the next general election in Britain in 2006.