A SOUTHAMPTON schoolboy has become the UK's youngest ever official voter - by casting his vote in the local council elections at the age of 13.

But now an investigation is being called for by one of the south's MPs into the ballot box blunder, amid concerns that the electoral system is open to abuse.

Only those aged 18 or over are eligible to vote following a change in electoral law 33 years ago.

Astonishingly, polling station officials waved teenager Jonathan Williams through after checking his passport against the polling card that had been sent to him in error. He was also told how to cast his vote.

Determined to test out just how watertight the voting process was, his father Alan took Jonathan along to the polling station just before it closed on Thursday night to see if the youngster would be challenged.

The lad, from Rownhams, Southampton, was allowed to proceed to the voting booth.

Romsey MP Sandra Gidley, whose constituency covers the area, wants to know why polling station officials let the schoolboy vote. She has also offered to pursue the case on behalf of Jonathan.

Mrs Gidley said: "Having presented the passport I'm surprised it was allowed. I find it startling that he pointed out he was under 18 and they still allowed him to vote.

"This makes the system open to abuse. All those involved in politics want to stamp this out. We want the system to be beyond reproach.

"Luckily I don't think it is a widespread problem."

Architect Mr Williams deliberately decided not to inform the council of the error it made in sending his son a polling card, to see how watertight the process was.

At 8.58pm, two minutes before their polling station at the community centre in Horn's Drove closed, the pair walked in to place their vote for the Chilworth, Nursling and Rownhams ward.

Mr Williams, 53, said: "I did this deliberately. We got our usual polling cards and there it was Jonathan Mark Williams. We looked at it a couple of times and decided it was genuine.

"We marched in at two minutes to nine and showed his passport.

"At the end of a long, long day they checked out the details and allowed him to vote.

"I'm aware of the ramifications for security. It begs the question, are the processes in place of sufficient stature? I have never heard of this happening before. To give a 13-year-old the right to vote is strange.

"If the result had been hung on one vote it would have massive ramifications.

"This should not happen in the first place. I thought they would tell me to go away."

The invalid vote could have had serious ramifications, including a fresh election at expense to taxpayers had the result been split by only one vote.

As it was, the true blue constituency was a Conservative walkover with three Tory candidates winning the three seats up for grabs.

At 1,242 votes, Councillor John Hall, who did not want to comment on the incident, polled the most support but only 12 votes ahead of his party colleague Nigel Anderton.

The Electoral Com-mission, an independent body whose aim it is to increase public confidence in the democratic process, was also not prepared to comment on individual cases and said it was an administrative issue for the returning officer.

Meanwhile, a spokeswoman for Test Valley Borough Council said they would look into the matter only if Mr Williams contacted them.

"If the individual concerned would like to contact our electoral services with the details we will look into it," she said.

"We go with the information on the electoral registration form. If there is no indication given of the person's age then we will take it that they are 18.

"We cannot comment on what might have occurred in the polling station.

"We have 87,500 people eligible to vote across the borough. We are at pains to make sure the register is accurate and incidents of this type are very rare."

Meanwhile Jonathan, a pupil at The Mountbatten School in Romsey, was remaining coy about his first taste of representative democracy.

The Daily Echo paperboy said: "I think it is quite strange. I did not have a clue what to do. I am now hoping to be able to drive down to the pub!"