Image copyright Getty Images

16-year-olds would get a vote in a second Brexit referendum under a Labour government.

That's according to John McDonnell - Labour's shadow chancellor.

Speaking to Radio 1 Newsbeat ahead of a vote on Labour's Brexit policy at party conference, Mr McDonnell says "if you're 16, we want you to have a vote".

"The most important thing for 16-year-olds is - let's give them the vote, let's trust them," he adds.

Labour have previously said in their 2017 election manifesto that they would "reduce the voting age to 16" from 18 - but with no reference to a second referendum.

John McDonnell - the second most important politician if Labour form a government - says he wants 16-year-olds to "participate in a referendum" where there will be an option of Remain or leaving the EU with an agreed deal.

"I'd like them to vote Remain, but that's part of the debate we've got to have," he says.

In Scotland, 16 and 17-year-olds voted for the first time in the Scottish independence referendum in 2014.

A bill was then passed in 2015, lowering the voting age to 16 for local and Scottish parliament elections.

Image caption Some delegates at Labour Party conference agree with the idea of lowering the voting age to 16

Give them a voice

Becky Gittens, 24, says now is the right time to give 16-year-olds a voice in the argument.

"Since 2016, we've been making decisions that will affect 16-year-olds more than it will affect 65-year-olds who have the vote.

"Which isn't an argument for disenfranchising older people, but it's definitely an argument to enfranchise younger people."

Anthony Tucker, 23, says Brexit "is a decision that's going to have an effect" for the next 30 to 40 years.

"I think a lot of 16 and 17 year-olds are going to be very angry if they don't get a chance to shape the future they're ultimately going to live in."

Image copyright Hani Mustafa Image caption Hani Mustafa thinks giving 16-year-olds the vote in another referendum would be unfair

Not everyone agrees

For Hani Mustafa, an 18-year-old Brexit supporter, "it wouldn't be fair".

Hani's not in favour of a second referendum "because it wouldn't really solve anything" and would do nothing "to resolve the tension".

But if there was to be one - "it would have to be the same question, same legislation, same rules and same conditions".

"If 16-year-olds couldn't vote in the first one, it wouldn't be very fair if they had the choice in this one".

He says that he doesn't disagree with the wider idea of 16-year-olds having a vote - but would only consider supporting it if it applied in all elections - from local to national.

But Hani adds that he's "not convinced" that 16-year-olds are ready for it.

"Was I really in the best place to vote at 16 years old? No. I think it's one of those things to wait for."

In 2017, the then-Prime Minister Theresa May, ruled out lowering the voting age, saying 18 years was "right".

And the Liberal Democrats say on their website that they want to extend the right to vote in all elections and referendums to 16 and 17 year olds.

Newsbeat has contacted the Labour Party, Conservative Party and Liberal Democrat party for comment but they have not yet responded.

Follow Newsbeat on Instagram, Facebook, Twitter and YouTube.

Listen to Newsbeat live at 12:45 and 17:45 weekdays - or listen back here.