An invalid vote is a cast vote which is considered void. When assessing the validity of a vote, the most important factor is whether or not the intention of the voter can be clearly identified.
A vote in political elections is therefore considered invalid when:
- the ballot paper is not officially produced
- the ballot paper is valid for the wrong constituency
- the ballot paper contains no markings
- the intention of the voter is not clearly discernible
- the ballot contains additional clauses
In a postal vote, a ballot paper is rendered invalid if it is not received in an official envelope, or when the type and condition of the official envelope are such that they adversely affect the election choice. The percentage of invalid votes in German Bundestag elections since 1990 is around 1,6 percent of total votes cast.
Impact of invalid ballot papers
Invalid votes have the same impact on the election result as abstentions. As the delegation of mandates is conducted solely by means of clear and valid votes, invalid ballot papers and abstentions have no impact on the election result. The only difference is that invalid votes are listed in election statistics. It is diffiicult to determine whether an invalid vote was cast deliberately or by mistake in a classic paper ballot voting.
Invalid votes in online elections
In online elections it is also possible to cast an invalid vote. However, this can only occur if the voter marks the field labelled "cast invalid vote". In contrast to classic paper ballots, the casting of an invalid vote is most probably deliberate in online elections because voters must actively confirm the invalid vote. This is because their choice is shown one more time before finally casting the vote.
See also: Abstained Votes
, Voter Turnout