In 1948 , single transferable vote proportional representation on a state - by - state basis became the method for electing Senators , this had the effect of limiting the government 's ability to control the chamber and has helped the rise of Australian minor parties .
In 1948 , single transferable vote proportional representation on a state - by - state basis became the method for electing Senators . 
 This had the effect of limiting the government 's ability to control the chamber , and has helped the rise of Australian minor parties .