A good news story from the 2007 federal election is informal voting. It dropped compared with 2004 – substantially, and in every state. Just why is currently a mystery.

The total percentage went from 5.18 percent in 2004 to 3.95 in 2007.

After the 2004 election, the AEC had a good look at the issue. They found that seat by seat variables such as the number of candidates on the ballot paper, whether the seat was in a state with optional preferential voting at state elections (NSW and Qld), levels of education and proportion of electors from non English speaking backgrounds all played a part.

The table below ranks the seats at the 2007 election by proportion of informal votes. Other columns are voting system for the lower house at state level (optional preferential, compulsory preferential or Tasmania’s Hare-Clark), proportion of people in the electorate who, according to Parliament House Library, told the 2006 Census they “speak English not well or not at all” (this is shown as a rank out of 150) and number of names on ballot paper.

The first thing that stands out is that western Sydney yet again hogs the top spots. Most rank high in the “poor English” stakes as well, and seats up the top tend to have higher numbers of candidates than those down the bottom. (The average number of candidates across all seats was 7.0)

Victoria seems over-represented at the bottom of the list:

Seat State Voting system at state level Rank proportion of people with poor English Number of candidates on ballot paper Informal votes (%)
Blaxland NSW OPV 1 8 10.5
Watson NSW OPV 3 6 10.0
Chifley NSW OPV 26 9 8.7
Prospect NSW OPV 5 5 8.4
Fowler NSW OPV 4 4 8.3
Reid NSW OPV 2 7 8.2
Parramatta NSW OPV 28 10 7.0
Werriwa NSW OPV 29 6 7.0
Banks NSW OPV 18 6 6.8
Bennelong NSW OPV 21 13 6.6
Grayndler NSW OPV 13 7 6.4
Barton NSW OPV 12 4 5.9
Lindsay NSW OPV 66 8 5.9
Macarthur NSW OPV 74 7 5.7
Kingsford Smith NSW OPV 27 5 5.6
Murray VIC CPV 76 9 5.5
Throsby NSW OPV 46 4 5.5
Lyne NSW OPV 145 9 5.3
Leichhardt QLD OPV 80 11 5.3
Port Adelaide SA CPV 22 5 5.2
Lowe NSW OPV 11 4 5.2
Stirling WA CPV 35 9 5.2
Wentworth NSW OPV 71 11 5.2
Calwell VIC CPV 19 9 5.1
Lingiari NT CPV 95 5 5.1
Berowra NSW OPV 55 7 5.0
Mackellar NSW OPV 72 7 4.9
Charlton NSW OPV 112 8 4.9
Wakefield SA CPV 78 8 4.9
O’Connor WA CPV 124 11 4.9
Greenway NSW OPV 65 7 4.9
Forde QLD OPV 92 9 4.8
Swan WA CPV 43 10 4.8
Perth WA CPV 34 9 4.8
Rankin QLD OPV 52 7 4.7
Gorton VIC CPV 6 5 4.7
Newcastle NSW OPV 88 10 4.7
Hasluck WA CPV 73 8 4.6
Wills VIC CPV 15 7 4.5
Dobell NSW OPV 127 8 4.5
Fadden QLD OPV 77 9 4.5
Hunter NSW OPV 137 6 4.5
Page NSW OPV 141 10 4.5
Richmond NSW OPV 129 7 4.5
Fremantle WA CPV 51 8 4.4
Grey SA CPV 122 7 4.4
Hughes NSW OPV 37 5 4.4
Gellibrand VIC CPV 16 8 4.4
Gilmore NSW OPV 118 9 4.4
Oxley QLD OPV 31 6 4.4
Parkes NSW OPV 121 7 4.4
Herbert QLD OPV 104 9 4.4
Cowan WA CPV 39 9 4.3
Shortland NSW OPV 136 5 4.3
Sydney NSW OPV 25 7 4.3
McEwen VIC CPV 105 8 4.3
Kalgoorlie WA CPV 100 8 4.3
Makin SA CPV 62 7 4.3
Scullin VIC CPV 14 6 4.2
Flynn QLD OPV 128 9 4.2
Bradfield NSW OPV 36 6 4.2
Wide Bay QLD OPV 142 7 4.2
Cowper NSW OPV 130 6 4.1
Maribyrnong VIC CPV 7 6 4.1
Pearce WA CPV 101 9 4.1
Cunningham NSW OPV 53 7 4.1
Hinkler QLD OPV 114 6 4.1
Brand WA CPV 113 8 4.1
Blair QLD OPV 109 8 4.0
Mitchell NSW OPV 56 7 4.0
Cook NSW OPV 82 8 4.0
Barker SA CPV 89 6 4.0
Kennedy QLD OPV 87 7 4.0
Hindmarsh SA CPV 41 8 4.0
Batman VIC CPV 10 6 4.0
Riverina NSW OPV 83 5 4.0
Farrer NSW OPV 132 6 4.0
Dawson QLD OPV 107 6 4.0
Moncrieff QLD OPV 61 8 3.9
Corio VIC CPV 59 9 3.9
Kingston SA CPV 103 8 3.9
Bruce VIC CPV 8 7 3.9
Eden-Monaro NSW OPV 96 7 3.8
Mallee VIC CPV 84 6 3.7
Warringah NSW OPV 63 8 3.7
Paterson NSW OPV 139 8 3.7
Holt VIC CPV 32 6 3.7
Macquarie NSW OPV 144 8 3.7
Maranoa QLD OPV 123 6 3.7
Bendigo VIC CPV 148 9 3.7
Lalor VIC CPV 49 6 3.6
Longman QLD OPV 115 7 3.6
North Sydney NSW OPV 50 8 3.6
Sturt SA CPV 38 6 3.6
Calare NSW OPV 138 5 3.6
Robertson NSW OPV 116 7 3.6
McMillan VIC CPV 126 8 3.6
Bowman QLD OPV 99 6 3.5
Hume NSW OPV 108 6 3.5
Capricornia QLD OPV 134 8 3.5
Fairfax QLD OPV 143 8 3.5
Forrest WA CPV 120 8 3.4
Isaacs VIC CPV 24 7 3.4
Canning WA CPV 94 7 3.4
Hotham VIC CPV 9 7 3.4
La Trobe VIC CPV 97 7 3.4
Bass TAS H-C 125 7 3.4
McPherson QLD OPV 81 7 3.3
Moreton QLD OPV 23 7 3.2
Adelaide SA CPV 33 5 3.2
Braddon TAS H-C 149 6 3.2
Groom QLD OPV 102 9 3.2
Lyons TAS H-C 150 6 3.2
Gippsland VIC CPV 110 6 3.1
Bonner QLD OPV 70 7 3.1
Moore WA CPV 93 7 3.1
Petrie QLD OPV 90 7 3.1
Brisbane QLD OPV 69 7 3.1
Lilley QLD OPV 85 6 3.1
Aston VIC CPV 47 6 3.0
Fisher QLD OPV 131 6 3.0
Solomon NT CPV 57 6 3.0
Griffith QLD OPV 54 8 3.0
New England NSW OPV 146 6 3.0
Boothby SA CPV 75 8 3.0
Casey VIC CPV 91 6 2.9
Flinders VIC CPV 106 5 2.9
Dickson QLD OPV 133 7 2.9
Mayo SA CPV 140 6 2.8
Menzies VIC CPV 30 6 2.8
Tangney WA CPV 48 7 2.8
Franklin TAS H-C 135 6 2.8
Indi VIC CPV 111 6 2.8
Dunkley VIC CPV 98 5 2.7
Chisholm VIC CPV 20 6 2.7
Wannon VIC CPV 147 4 2.7
Higgins VIC CPV 42 8 2.6
Corangamite VIC CPV 119 6 2.6
Denison TAS H-C 86 6 2.6
Jagajaga VIC CPV 64 6 2.5
Goldstein VIC CPV 58 6 2.5
Ballarat VIC CPV 117 4 2.5
Fraser ACT CPV 60 7 2.4
Canberra ACT CPV 79 4 2.3
Melbourne Ports VIC CPV 44 6 2.2
Ryan QLD OPV 68 8 2.2
Kooyong VIC CPV 45 6 2.1
Deakin VIC CPV 40 6 2.1
Curtin WA CPV 67 7 2.0

Some people deliberately spoil their ballot paper (or leave it blank), but most informal votes are accidental.

This is a problem which could be substantially eradicated if we introduced optional preferential voting for the House of Representatives. If we did that, then we could relax the rules for what counts as a vote, for example a tick or cross in a box would do.

But the major federal parties aren’t keen on OPV, because each thinks it would benefit the other side.

They can’t both be right. The truth is probably that it would vary from election to election. In the current climate, of a high Green vote and few three-cornered contests (where both Liberal and National contest), OPV would benefit the Coalition parties because tens of thousands of Green votes would “exhaust” before reaching Labor.

But don’t hold your breath for OPV at federal elections.

In the meantime, we could find out what – if anything – the AEC did to cut informal votes by almost a quarter from 2004 to 2007 – and do more of it.