Analysis of Informal Voting, House of Representatives, 2010 Federal Election - Background

Updated: 30 May 2013

Voting requirements

Details on the history of formal voting requirements in Australia can be found in the AEC Electoral Backgrounder on Informal Voting, released in April 2010 (AEC 2010e). More detailed information regarding the formality principles applied at the 2010 House of Representatives election is available from the Ballot Paper Formality Guidelines for the 2010 federal election (AEC 2010a).

Under section 268 of the Electoral Act, ballot papers cast in House of Representatives elections are informal if:

  • they have not been authenticated by the initials of the presiding officer or the issuing officer, or by the presence of the official mark 3;
  • the ballot paper has no vote indicated on it;
  • subject to the exceptions noted below, the ballot paper does not indicate the voter's first preference for one candidate, and an order or preference for all the remaining candidates;
  • the ballot paper has any mark of writing on it by which, in the opinion of the Divisional Returning Officer, the voter can be identified; or
  • in the case of an absent vote – the ballot paper is not contained in an envelope bearing a declaration made by the elector under subsection 222(1) or (1A) of the Electoral Act.

If one box is left blank (meaning that there is no marking in the box at all) and all other boxes have been numbered in a consecutive sequence starting with the number '1', the ballot paper is formal (i.e. it is deemed that the voter's last preference is for the candidate where the square is blank). If two or more boxes on a House of Representatives ballot paper have been left blank, the ballot paper is informal.

If there are only two candidates on the ballot paper and the voter has placed a '1' in the box beside a candidate and either left the second box blank or inserted a number other than '2' in it, the ballot paper is formal (i.e. the voter is deemed to have indicated an order of preference for all candidates).

Ticks or crosses are not acceptable forms of voting for House of Representatives elections, and ballot papers containing ticks and/or crosses are informal.

Alterations to numbers will not make a ballot paper informal, provided the voter's intention is clear (for example, a number can be crossed out and another number written beside it). However, if a number is overwritten in a way that makes it impossible to read, the ballot paper is informal.

Key formality requirements in other Australian state and territory lower houses are summarised in Appendix A.

Categories of informal ballot papers

Tables 1 and 2 list the categories of informal ballot papers used for the 2010 House of Representatives election Informal Ballot Paper Survey, and indicate how these categories can be compared with categories used in the 2001, 2004 and 2007 surveys.

Explanations and coding notes relating to the 2010 informality categories are provided at Appendix B. While AEC staff were provided with instructions on how to categorise informal ballots, in some cases they may have differed in their interpretation of the categories (largely because some informal ballots exhibit characteristics that could place them in more than one category).

Table 1

Informality categories for the 2010 House of Representatives Informal Ballot Paper Survey
Category and subcategory
Category A: Blank ballots
Category B: Incomplete numbering (a)
   B-1: Number '1' only
      J-1: Number '1' only for first candidate on ballot paper
      J-2: Number '1' only for second candidate on ballot paper
      J-3: Number '1' only for third candidate on ballot paper
      J-4: Number '1' only for fourth candidate on ballot paper
      J-5: Number '1' only for fifth candidate on ballot paper
      J-6: Number '1' only for sixth candidate on ballot paper
      J-7: Number '1' only for seventh candidate on ballot paper
      J-8: Number '1' only for eighth candidate on ballot paper
      J-9: Number '1' only for ninth candidate on ballot paper
      J-10: Number '1' only for tenth candidate on ballot paper
      J-11: Number '1' only for eleventh candidate on ballot paper
   B-2: Number '1, 2' only
   B-3: Number '1, 2, 3' only
   B-4: Number '1, 2, 3, 4' only
   B-5: Number '1, 2, 3, 4, 5' only
   B-6: Number '1, 2, 3, 4, 5, 6' only
   B-7: Number '1, 2, 3, 4, 5, 6, 7' only
   B-8: Number '1, 2, 3, 4, 5, 6, 7, 8' only
   B-9: Number '1, 2, 3, 4, 5, 6, 7, 8, 9' only
Category C: Ticks and crosses
Category D: Other symbols (e.g. alphabetic characters, zeros etc.)
Category E: Non-sequential numbering
   E-1: Unique first preference but repeated numbers within sequence, all squares completed
   E-2: Unique first preference but repeated numbers within sequence, not all squares completed
   E-3: Repeated number '1's
   E-4: Missing numbers within sequence, number '1' missing and no repeated numbers
   E-5: Unique first preference but missing numbers within sequence, no repeated numbers
   E-6: Other non-sequential numbering
Category F: Scribbles, slogans or other protest vote marks
   F-1: Scribbles/slogans
   F-2: Candidate names changed
   F-3: Other protest vote marks
Category G: Illegible numbers
   G-1: Illegible numbers, first preference clear, second preference not clear
   G-2: Illegible numbers, first and second preferences clear
   G-3: Illegible numbers, first preference not clear
Category H: Voter identified
Category I: Other informal ballot papers

(a) As the maximum number of candidates on a ballot paper for the 2010 House of Representatives election was 11, there are nine subcategories for incompletely numbered informal ballots (B-1 to B-9), and eleven subcategories for ballots with a number '1' only (J-1 to J-11).

Table 2

Comparability of informality categories for 2001, 2004, 2007 and 2010 House of Representatives election Informal Ballot Paper Surveys
Categories/subcategories used in 2010 survey Comparable category used in previous surveys
2001 2004 2007
Blank (A) Yes ('Blank') Yes (A) Yes (A)
Incomplete numbering (B) Not completely reported Yes (B) Yes (B)
   Number '1' only (B-1) Yes ('Number 1 only') Yes (B-1) Yes (B-1)
   Candidates for number '1' only ballots (J-1 to J-11) Not reported Not reported Not reported
   Other incomplete numbering subcategories (B-2 to B-9) Included in 'Other' Yes (B-2 to B-12) Yes (B-2 to B-11)
Ticks and crosses (C) Yes ('Ticks and crosses') Yes (C) Yes (C)
Other symbols (D) Not reported Yes (D) Yes (D)
Non-sequential numbering (E) Yes (sum of 'Langer Style votes' (a) and 'Nonsequential votes') Yes (E) Yes (E)
   Unique first preference but repeated numbers within sequence, all squares completed) (E-1) Yes ('Langer Style votes') Not reported Not reported
   Other subcategories for nonsequential numbering (E-2 to E-6) Yes ('Non-sequential votes'; no subcategories reported) Not reported Not reported
Scribbles, slogans or other protest vote marks (F) Yes ('Marks' (b)) Yes (F) Yes (F)
   Subcategories for scribbles/slogans/other protest vote marks (F-1 to F-3) Not reported Not reported Not reported
Illegible numbers (G) Yes ('Slogans making numbers illegible' (c)) Yes (G) Yes (G)
   Subcategories for illegible numbers (G-1 to G-3) Not reported Not reported Not reported
Voter identified (H) Yes ('Voter identified') Yes (H) Yes (H)
Other Yes ('Other' (d)) Yes (I) Yes (I)

(a) Langer-style votes refer to ballots with preferences marked in the pattern '1, 2, 3, 3, 3…'. More information on the historical background for Langer-style votes is provided in the AEC Electoral Backgrounder on Informal Voting.

(b) This category referred to ballot papers with no preference, or partial preferences, where there were slogans, written comments or marks on the ballot paper (AEC 2003).

(c) This category referred to all those ballot papers where slogans, writing or comments have been made and the words or marks interfere with the preferences in such a way that the numbering could not be deciphered.

(d) This category contained informal ballot papers that could not be categorised into any of the other categories used for the 2001 survey. Typically, it consisted of ballot papers that had insufficient preferences expressed.

Source: AEC 2003; AEC 2005a, AEC 2009.


3. A ballot paper to which this situation applies is formal if the Divisional Returning Officer responsible for considering the question of the formality of the ballot paper is satisfied that it is an authentic ballot paper on which a voter has marked a vote and the officer has endorsed the ballot paper with the words 'I am satisfied that this ballot paper is an authentic ballot paper on which a voter has marked a vote.'