Electoral fraud, also known as voter fraud, and sometimes referred to as election manipulation, election scam, vote rigging, or election stealing, is illegal interference with the process of an election, either by increasing the vote share of a favored candidate, depressing the vote share of rival candidates, or both. It differs from but often goes hand-in-hand with voter suppression. What exactly constitutes electoral fraud varies from country to country, though the goal is often election subversion.

Electoral legislation outlaws many kinds of election fraud, also at but other practices violate general laws, such as those banning assault, harassment or libel. Although technically the term "electoral fraud" covers only those acts which are illegal, the term is sometimes used to describe acts which are legal, but considered morally unacceptable, outside the spirit of an election or in violation of the principles of democracy. Sham elections, featuring only one candidate, are sometimes classified as electoral fraud, although they may comply with the law and are presented more as referendums/plebiscites.

In national elections, successful electoral fraud on a sufficient scale can have the effect of a coup d'état, protest, or corruption of democracy. In a narrow election, a small amount of fraud may suffice to change the result. Even if the outcome is not affected, the revelation of fraud can reduce voters' confidence in democracy.

Law Because U.S. states have primary responsibility for conducting elections, including federal elections, many forms of electoral fraud are prosecuted as state crimes. State election offenses include voter impersonation, double voting, ballot stuffing, tampering with voting machines, and fraudulent registration. Penalties vary widely by state and can include fines, imprisonment, loss of voting rights, and disqualification from holding public office.

The U.S. federal government prosecutes electoral crimes including voter intimidation, conspiracy to commit election fraud, bribery, interference with the right to vote, and fraud related to absentee ballots in federal elections.

In France, someone guilty may be fined and/or imprisoned for not more than one year, or two years if the person is a public official.

Electorate manipulation

Electoral fraud can occur in advance of voting if the composition of the electorate is altered. The legality of this type of manipulation varies across jurisdictions. Deliberate manipulation of election outcomes is widely considered a violation of the principles of democracy.

Artificial migration or party membership In many cases, it is possible for authorities to artificially control the composition of an electorate in order to produce a foregone result. One way of doing this is to move a large number of voters into the electorate prior to an election, for example by temporarily assigning them land or lodging them in flophouses. Many countries prevent this with rules stipulating that a voter must have lived in an electoral district for a minimum period (for example, six months) in order to be eligible to vote there. However, such laws can also be used for demographic manipulation as they tend to disenfranchise those with no fixed address, such as the homeless, travelers, Roma, students (studying full-time away from home), and some casual workers.

Another strategy is to permanently move people into an electoral district, usually through public housing. If people eligible for public housing are likely to vote for a particular party, then they can either be concentrated into one area, thus making their votes count for less, or moved into marginal seats, where they may tip the balance towards their preferred party. One example of this was the 1986–1990 Homes for votes scandal in the City of Westminster in England under Shirley Porter.

Immigration law may also be used to manipulate electoral demography. For instance, Malaysia gave citizenship to immigrants from the neighboring Philippines and Indonesia, together with suffrage, in order for a political party to "dominate" the state of Sabah; this controversial process was known as Project IC. In the United States, supporters of the far-right Great Replacement conspiracy theory claim that Democrats want to extend suffrage to undocumented immigrants to sway elections away from the Republicans.

A method of manipulating primary contests and other elections of party leaders are related to this. People who support one party may temporarily join another party (or vote in a crossover way, when permitted) in order to elect a weak candidate for that party's leadership. The goal ultimately is to defeat the weak candidate in the general election by the leader of the party that the voter truly supports. There were claims that this method was being utilised in the UK Labour Party leadership election in 2015, where Conservative-leaning Toby Young encouraged Conservatives to join Labour and vote for Jeremy Corbyn in order to "consign Labour to electoral oblivion". Shortly after, #ToriesForCorbyn trended on Twitter.

Disenfranchisement

The composition of an electorate may also be altered by disenfranchising some classes of people, making it very difficult or impossible for members of these classes to vote. Some U.S. states have enacted provisions that raised general barriers to voter registration, such as poll taxes, literacy and comprehension tests, and record-keeping requirements, which in practice were applied against minority populations to discriminatory effect. From 1900 through the 1960s, most African Americans in the southern states comprising the former Confederacy were disenfranchised by such measures. Corrupt election officials may misuse voting regulations, such as a literacy test or requirement for proof of identity or address, to make it difficult or impossible for their targets to cast a vote. If such practices discriminate against a religious or ethnic group, they distort the political process so greatly that the political order becomes grossly unrepresentative, as in the post-Reconstruction or Jim Crow era until the Voting Rights Act of 1965. Felons have been disenfranchised in many states as a strategy to prevent African Americans from voting.

Other groups can also be disenfranchised by certain electoral rules. For example, requiring people to vote within their electorate may disenfranchise active military personnel, prison inmates, students, hospital patients or anyone else who cannot easily appear in their home electorate. Polling can be held on inconvenient days, such as during the working week or on holy days for religious groups, like the Sabbath or other holy days of a religious group which teach that voting is prohibited on such a day. Communities may also be effectively disenfranchised if polling places are situated in areas perceived by voters as unsafe, or are not provided within reasonable proximity (rural communities are especially vulnerable to this).

In some cases, voters may be individually invalidly disenfranchised, which constitutes electoral fraud. A legitimate voter may be "accidentally" removed from the electoral roll, making it difficult or impossible for the person to vote.

Attempts at disenfranchisement tend to favor political groups currently in power. In the Canadian federal election of 1917, during the Great War, the government led by the Union Party passed the Military Voters Act and the Wartime Elections Act. The Military Voters Act permitted any active military personnel to vote only for a party (and not an individual candidate) and allowed that party to decide in which electoral district to place that vote. It also enfranchised those women who were directly related or married to an active soldier. These groups were believed to be disproportionately in favour of the Union government, who were campaigning in favor of conscription. The Wartime Elections Act, conversely, disenfranchised particular ethnic groups assumed to be disproportionately supportive of the opposition Liberal Party.

Division of opposition support Stanford University professor Beatriz Magaloni described a model governing the behaviour of autocratic regimes. She proposed that ruling parties can maintain political control under a democratic system without actively manipulating votes or coercing the electorate. Under the right conditions, the democratic system is maneuvered into an equilibrium in which divided opposition parties act as unwitting accomplices to single-party rule. This allows the ruling regime to abstain from committing electoral fraud.

Preferential voting systems such as score voting and single transferable vote, and in some cases, instant-runoff voting, can reduce the impact of systemic electoral manipulation and political duopoly.

Intimidation Voter intimidation involves putting undue pressure on a voter or group of voters so that they will vote a particular way, or will not vote at all. Absentee and other remote voting schemes can be more open to some forms of intimidation, as the voter does not have the protection and privacy of the polling location. Intimidation can take a range of forms including verbal, physical, or coercion. This was so common that in 1887, a Kansas Supreme Court in New Perspectives on Election Fraud in The Gilded Age said "[...] physical retaliation constituted only a slight disturbance and would not vitiate an election."

Violence or threats of violence In its simplest form, voters from a particular demographic or known to support a particular party or candidate are directly threatened by supporters of another party or candidate, or another group hired to do so. For example, supporters of a particular party make it known that if a particular village or neighborhood is found to have voted the 'wrong' way, reprisals will be made against that community. Another method is to make a general threat of violence, for example, a bomb threat, which has the effect of closing a particular polling place, thus making it difficult for people in that area to vote. Polling places and areas may be targeted for vandalism, destruction, or threats thereof if they are known to support a particular party or candidate.

One notable example of actual violence was the 1984 Rajneeshee bioterror attack, where followers of Bhagwan Shree Rajneesh deliberately contaminated salad bars in The Dalles, Oregon, in an attempt to weaken political opposition during county elections. Historically, this tactic included lynching in the United States to intimidate potential African American voters in some areas.

Legal threats Voters may be falsely told they are not legally entitled to vote, or that they are legally obliged to vote a particular way. Voters who are already not confident about their entitlement to vote may also be intimidated by real or implied authority figures who suggest that those who vote when they are not entitled to will be imprisoned, deported or otherwise punished. Coercion Employers can coerce a voter's decision, for example through explicit or implicit threats of job loss.

Disinformation People may distribute false or misleading information in order to affect the outcome of an election. For example, in the Chilean presidential election of 1970, the U.S. Central Intelligence Agency used "black propaganda"—materials purporting to be from various political parties—to sow discord between members of a coalition to separate socialists and communists.