Staff at polling stations in the UK have been advised to stop people taking "selfies"' inside voting booths to prevent them being prosecuted.
The Electoral Commission believes the latest craze of taking photos of yourself on a smartphone, which has been embraced by David Cameron and Barack Obama, could inadvertently reveal how someone has voted in this week's local and European elections.
According to Section 66 of the Representation of the People Act, it is a criminal offence to reveal how someone has voted or will vote, as well as to communicate the unique serial number on a ballot paper.
In sending out guidelines to election staff, the Electoral Commission said: "The law relating to obtaining information in polling stations and disclosing such information is complex.
"Given the risk that someone taking a photo inside a polling station may be in breach of the law, whether intentionally or not, our advice is that you should not allow photos to be taken inside polling stations."
Anyone who is found to be in breach of the law could face a £5,000 fine or up to six months in prison.
Local authority officials say the biggest concern is voters taking selfies and then uploading them to social networks such as Facebook without realising the image could contain sensitive information.
The Electoral Commission also says that there are complications with the application of the law, which depends on a number of factors, including whether the image was shared with others and its contents.
The Commission says it is for this reason and the protection of voters that it is advising against any photography being allowed inside polling stations.
However, Katie Ghose, chief executive of the Electoral Reform Society, believes the chance to take a selfie while voting is an opportunity to encourage more of the younger generation to go to the polls.
"The fact we all have a say in who gets to run the country ought to be a cause for celebration.
"At a time when more and more people are turning away from politics, anything which brings a sense of occasion to election day ought to be encouraged," she said.
"Of course it's vital that people's privacy isn't invaded in the polling booth. But selfies could be a fun addition to the voting day ritual, especially for young people who are least likely to vote.
"Rather than seeking to take the fun out of politics we should be doing everything we can to make it more attractive to vote.
"And if other countries can allow selfies whilst maintaining the secrecy of the ballot, so should we."
Elections in the Netherlands in March saw both regular citizens and politicians posting selfies from inside the polling booth, complete with the Twitter hashtag 'stemfie'; a combination of the Dutch word to vote, 'stemmen' and selfie.