This article is from the soc.culture.australian FAQ, by Stephen Wales with numerous contributions by others.
* How to Vote
Each Australian citizen should be registered on the electoral rolls at
the age of 18. Voting in Australia is compulsory. In practice, this
means that you have to go to a voting station, receive voting papers
and get your name ticked off. You do not have to cast a valid vote.
Typically "informal" votes range from 5-10% of the vote.
People who were granted permanent resident status and were enrolled to
vote before 1984 may continue to do so. Those who neglected to enroll
to vote before 1984 cannot vote regardless of when they're permanent
residency was granted, unless they become citizens.
Votes usually cast their vote at a local polling station in their
electorate. If you are not in your electorate on the day of the vote,
you can go to any polling station and cast an "absentee" vote. If you
do not think you will be able to go to a polling station on the day,
you can cast a postal vote earlier.
To cast a postal vote overseas, write to the nearest embassy or
consulate, or call them. They will send you a form to fill in (which
has to be witnessed by an Australian citizen). They then send you the
postal vote slip, which you have to return by a date usually before
the election.
[SW] You can have yourself removed from the electoral rolls if you
intend to leave the country for in excess of 3 years.
* Electoral Structure and Voting System.
[I got several good summaries, so I've included them all for the
moment. The next FAQ maintainer might like to compress them. AN]
[PD, AN]
Australia is divided into 147 federal electorates. Each electorates
elects a member to the House of Representatives. The voting system is
compulsory preferential voting. "Preferential Voting System" is used
in all Lower Houses in Australia except Tasmania. Also used in the
Upper House (Legislative Council I think) in Victoria (whose upper
house is made of "super- electorates") Historically, it was brought in
(there is a little supposition here) because at the time of Federation,
Conservative politic was divided into two Parties; Free Traders and
Protectionists while the Left was only the Labour Party. The
Conservatives didn't want what occurs to the left in England now to
affect them; namely with a First past the post system, Labour could
have won office with, say, 40% of the vote.
Anyway, the philosophy behind it is that the most preferred candidate
is elected. (Or more precisely the least preferred candidate is not
elected!) When voting the elector must number all candidates from most
preferred to least preferred (ie say 1-4 for four candidates), i.e. not
put a cross next the name in a first past the post system. Primary
votes are counted, i.e. who got no 1. If there is not an absolute
majority of votes for some candidate (winner outright), then candidate
with least votes has their preferences distributed. To do this votes
of least popular candidate ONLY, are given in full to voters' 2nd
preference. If there is still not an absolute majority then 2nd least
popular candidate's next preferences are redistributed. In the worst
case, no candidate will get over 50% until there are only 2 candidates
remaining, by which stage there must be a winner. If there is a draw
between 2 candidates at the end (50% each) the winner is drawn "out of
the hat."
Example: round 1 (first preferences) (100 votes)
Fred 35 <- less than 50% Must distribute preferences
Jane 30
Paul 25
Bronie 10 <- least votes; eliminated; goto no 2's on
on ballot; Paul 7; Fred 2; Jane 1
Fred 35+2 = 37
Jane 30+1 = 31 <- eliminated because of fewest votes
Paul 25+7 = 32
Round 3
Fred 35+2+12=49
Paul 25+7+19=51 <- Paul elected (This example shows why
how the preferences are distributed and why the
political parties have scrutineers watching the vote
counting (ie to count how many preferences))
 
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