These include bribery, treating, undue influence, personation, making false declarations as to election expenses, false statements about the personal character or conduct of a candidate, and many more (see ). Some are prosecuted as criminal offences. Sanctions for those found guilty are draconian.

Election law is contained in the Representation of the People Act 1983 (RPA 1983) which, together with other statutes and sets of regulations, govern the conduct of candidates, their election agents, campaign supporters, voters, political parties, and returning officers and their staff, the officials running the election process. The rules of conduct, which have to be complied with strictly, have little room for discretionary manoeuvre.

Election petitions: a rare challenge

Challenges to the results of elections are by an election petition, an antiquated process containing pitfalls for the unwary. The RPA 1983 provides that no parliamentary or local election can be declared invalid by reason of an act or omission of the returning officer, or other person, in breach of his official duty, if the election court is satisfied that the election was conducted substantially in accordance with the law of elections, and that any act or omission did not affect the result. For a successful challenge to be mounted, relying on breaches of duty on the part of returning officer or others, the election result is likely to be a narrow one, where the court is unable to be satisfied that the result was not affected. Results of parliamentary elections are not normally narrow.

Since the Second World War, there has been one case (eventually conceded in court; hence no reported decision). This was the Winchester election in May 1997, where the Liberal Democrat candidate won by two votes against the Conservative candidate. However, 54 ballot papers had not been stamped or perforated as required by law. The Divisional Court was satisfied that the result of the election was likely to have been affected and the election was declared void. (In fact, at the resulting by-election, the Liberal Democrat candidate won with a majority of 21,000 votes.)

Challenges to parliamentary election results on the grounds of corrupt or illegal practices are rare. In 2010, a parliamentary election was declared void by an election court, on the grounds that the Labour candidate was guilty of the illegal practice of making false statements about the personal character of the petitioner, contrary to s 106 of RPA 1983. The court found that the candidate had made allegations of fact, falsely suggesting he was willing to condone threats of extremist Muslim violence, in pursuit of personal political advantage. The decision was upheld by the Divisional Court. This was the first parliamentary election petition founded on s 106 since 1911.

‘Roll stuffing’: easy to commit, difficult to detect

Several challenges to local election results have been made on the grounds of election fraud on the part of candidates, or their agents. They were: 2005 in Birmingham, 2008 in Peterborough and Slough, 2010 in Bradford, 2013 in Woking and most recently in Tower Hamlets. The frauds were often perpetrated by very late multiple applications to go on the electoral register from ‘ghost’ voters, from particular addresses, where the voters did not exist, or where they did not reside (a practice known as ‘roll stuffing’). Applications for postal votes were made at the same time. The resulting votes were fraudulent, and the candidates or their agent were guilty of personation, and other corrupt practices.

In the Slough case, the Election Commissioner Mr Richard Mawrey QC said in his judgment: ‘There is no reason to suppose that this is an isolated incident. Roll stuffing is childishly simple to commit and very difficult to detect. To ignore the probability that it is widespread, particularly in local elections, is a policy that even an ostrich would despise.’

Election fraud of this type has been very difficult to detect, because it often involves applications to go on the register and for postal votes that can now be made at any time up to 11 days before poll, when the registration officers have neither the time nor resources to investigate bogus registrations.

Fortunately, election fraud at parliamentary elections does not seem to have occurred, or has not been discovered. It remains to be seen whether recent changes to the law to require individual voter registration will further discourage those who may be tempted to resort to fraud at the ballot box on 8 June.

Contributor Richard Price OBE QC, 4-5 Gray’s Inn Square, specialises in election and public law