Plans to put photographs of candidates on ballot papers are unlikely to develop after researchers claimed it would turn politics into a beauty pageant. The Westminster Government has toyed with the idea as a way of reversing falling voting levels.

But political experts from Strathclyde University believe it would lead to able candidates being ditched in favour of more attractive opponents. Dr Robert Johns and Dr Mark Shephard of the University's Department of Government carried out research into the proposals. They asked a cross-section of 4,000 voters to choose between pairs of candidates.

The researchers found that the impact of aesthetically-pleasing candidates would be enough to swing the result in marginal constituencies.

Johns said: "A candidate's appearance is currently just one of many factors at play in elections, but if photos were included in ballot papers it would be much more significant. We carried out hypothetical elections using ballot papers featuring candidates who were rated quite high and quite low in terms of looks.

"We found that when those pairs were matched we found differences of around 4% in favour of the more attractive candidate.

"It would be enough to swing plenty of marginal constituencies."

Johns added that the advantage was certainly with the younger, more good-looking candidate.

He said: "The effect was magnified when it was a race between a man and a woman. A young man against an older woman, or vice versa, had a big advantage."

In the past decidedly unglamorous politicians such as Winston Churchill in the UK and Abraham Lincoln in the US achieved high office and served with distinction.

But Johns feels it is becoming increasingly difficult for less photogenic politicians to emulate their achievements.

"The knock-on effect would be that parties would pay far greater attention to who they were choosing and how they presented themselves.

"Selection committees would find themselves looking for ever younger, more attractive candidates. The pronounced youth advantage would undoubtedly lead to some people dusting down older more flattering pictures."

A spokesman for the Electoral Commission confirmed there were no current plans to introduce photographs on ballot paper.

But he added: "We believe that the ballot paper is one of the key components in the electoral process, and that it should be as user-friendly as possible."