Young people are being neglected by a government which does not respect them, Liberal Democrat leader Charles Kennedy has said in a speech to students.
Mr Kennedy says young people are naturally liberal
Mr Kennedy said Labour's "Respect" agenda was too narrow and more trust had to be placed in young people.
He said election reforms currently going through Parliament should be used to cut the minimum voting age to 16.
"We want young people to be part of the system - not outside looking in," he said at the London School of Economics.
'Rights and responsibilities'
Mr Kennedy said the generation sometimes described as "Thatcher's children" - who were teenagers in the 1980s and now coming to political prominence - were "liberal - socially and economically".
And there were signs that those at school and university during Tony Blair's premiership were also backing the Liberal Democrats, he said.
He highlighted how the Lib Dems had been backed by 26% of voters aged between 18 and 24 at the last election - higher than the party's overall 22% share of the vote.
And the Lib Dems had come top of a mock general election organised by the Hansard Society in 2,000 schools.
They won 42% of the vote, with the Conservatives receiving 24% and Labour 17%.
Ready to vote?
Mr Kennedy said citizenship lessons at school were being undermined by keeping the voting age at 18.
"At 16, this Labour government is quite happy to take your taxes, to let you raise a family, to let you join the Army - but not to let you vote," he said.
"Well, I say what about that right to vote going with those responsibilities?
"I say that, by 16, people are ready to vote, ready to make their personal choice and ready to take part in choosing who governs them."
Mr Kennedy said the voting age could have been changed in the Electoral Administration Bill, which is currently before Parliament.
But Labour and the Tories did not have the foresight or courage to back the move, he argued.
The bill would, however, lower the age at which people can be parliamentary candidates from 21 to 18.
Mr Kennedy said proportional representation was also needed so first-time voters did not think their vote was being wasted, he argued.
The Lib Dem leader said his party could appeal to young voters because of its opposition to university top-up tuition fees, its commitment to the environment and civil liberties.
A report from the elections watchdog last year said the voting age should stay at 18 and there was not clear majority support for a change.
Electoral Commission Sam Younger said: "The evidence from the review suggests that while many young people under-18 would feel ready to vote, there are just as many who feel that 16 is too young."