The first three sentences and the last four sentences in GUEST,John Gray in Oz' posting are factual while the rest are partisan and only arguable. However...

I happened to be in SC during the summer and autumn leading to the election of Bill Clinton and found it interesting to compare the two systems. I found many who rather agreed with the aphorism, common in Australia, "It doesn't matter who you vote for, it's always a politician that gets in." When they found we had compulsory voting, and that you were fined if there was no record of you voting or having a valid excuse, most I talked with thought it would be wonderful to have the same system in America. I then confused them a little by telling them that many Australians used all the arguments presented above in the thread to justify a preference for noncompulsory voting.

My own preference is for compulsory voting, as it forces everyone to take some level of responsibility for the consequences. I realise that many duck any notion of responsibility in this matter and can even express it on the ballot papers. Because we use a 'preferential voting' system (I can bore you with the details another time) you must put a number in each candidate's box on the paper; that's the simplest version but it can get a bit more complex. If you just number them in consecutive order down the list, it's counted as valid but is called a "donkey vote"; their proportion of the total is mulled over by psephologists. If you mark any part of the ballot paper outside the boxes (by writing derisive insults, for example) or use comments in the boxes, the ballot paper is classified "Invalid" and not counted to any candidate; the proportion of these in the total is described as "the protest vote" and is also mulled over by psephologists.

Many of my American friends who thought compulsory voting was a generally good idea were not so sure when I told them that this meant that Australians were required to inform the Australian Electoral Commission (an arm of the Commonwealth Govt also used by State and Municipal Govts) of any change of address. The independence of the AEC ensured no nonsenses of the types we heard about a couple of years ago but they had to have a record (in the public domain) of where to mail the notification you were to be fined.

I'm not sure compulsory voting, compared with noncompulsory votin, would have a great difference in the results but I think it would certainly change the tactics used by both politicians and voters. I regard myself as unwilling to allow any arm of govt to arrogate to itself any responsibility I think I should exercise. I want to vote and I construct my tactics accordingly and then go and vote, even when I have to list 163 candidates in descending order of preference on a ballot paper the size of a decent tablecloth.

Cheers, Rowan