One of the highlights of the BBC's election coverage was the Question Time special, when the three main party leaders were put on the spot by members of the public.
Young people asked most of the questions
But more than 70 people called to complain - not about the politicians, but about the audience. They said there were far too many young people for it to be representative.
Graham Moores said: "The camera panned around the audience and I was dismayed to see it was so young. It's well-known that statistically the young vote is more left than the grey vote." And Terry Henebery commented: "A balanced audience? I think not."
Ric Bailey, the executive editor of Question Time, answers viewers' concerns.
How did you select your audience?
We have a lot of balances to achieve in putting together an audience for Question Time and that's particularly true during an election period where there are actually legal obligations in terms of balance.
The most important one is political balance. We have to ask questions about people's background, about their political allegiance, their voting history and so on. We have to make absolutely sure that all the parties, not just the three main parties, are represented in the audience.
We want to make sure we have ordinary voters there, we have a smattering of party activists and we have people who haven't yet made up their mind.
Ric Bailey: Could have had more older people
We're also looking for a gender balance, we're looking for ethnicity balance we're looking for a balance of social groups and we're looking for an age balance.
Looking back at the programme I think that we got most of the balances pretty well right. However, I think we were probably under-representative among older people, I accept that.
But I think we did achieve a very lively programme in which there were lots of young people who contributed their views and a few older people as well.
It's interesting to get criticised from this angle because one of the things you are trying to do in political programmes very often is to attract younger voters and younger viewers. It's the one thing that everybody wants to do and Question Time attracts more young people to watch it than any other political programme and we're very proud of that.
Of the 50 questions asked, about 80% were from people under 35. Can you see why viewers might have found that a bit odd?
You can't always tell who's going to ask the questions. We don't select the questions or who speaks on the basis of their age and as it turned out there was a very high degree of young people asking questions.
If you're looking for a spontaneous debate you can't regulate that audience and pick people according to other criteria. You pick people according to whether they've got their hands up or not and according to what views they have and you can't actually regulate that.
Audiences are carefully vetted
I'm accepting there were probably more young people who spoke than would be representative but Question Time is not representative; that's a mistake some people often make. They expect it to be a microcosm of the population as a whole. It's not. If it was, at least half the audience wouldn't be interested in politics and that wouldn't make much sense at all.
There was an asylum seeker in the audience - was he planted there?
Absolutely not. One of the things we tried to do for this programme is to make sure the people in the audience were what we would describe as ordinary voters - in other words, they weren't people from particular campaigns or who had particular hobbyhorses.
You can't completely exclude people like that because lots of ordinary voters do have real interests that they want to get across once they get in the audience.
I can't talk about individual members of the audience but we do a very detailed interview with everyone, we know their backgrounds very clearly and all I can say is that we were happy that the members of the audience - and this one is particular - were legitimate members of the audience.
How about Diana Church, who became the story of the night with her question about the problems getting appointments with GPs?
It was a classic Question Time "beneath the radar" question, really. It wasn't the sort of question you'd have picked out from those who put in their questions before the programme necessarily.
She happened to say it, she got a particular reaction from Tony Blair and we sensed at the time people around her in the audience saying: "Yes, I know something about that."
And so you suddenly felt that there was a story there and the Prime Minister came to that completely fresh and was slightly caught out by it. But we certainly didn't plant her. We didn't know she was going to say that.
David Dimbleby described the audience as "carefully chosen to be a cross section of voters". Was he right?
I was really happy with the audience and was very happy with the way the programme worked. I think a lot of commentators said it was the biggest and most interesting TV event of the election campaign.
As I've said, if we were absolutely going for the perfect balance then we might have had more older people in the audience. But we are juggling lots of different balance acts with the audience for Question Time and you can't always get all of them exactly right.
Are things easier for Question Time where there isn't an election?
Clearly in election time it's very strict in terms of proportions. One of the reasons Question Time goes around the country and comes from different places each week is to give licence fee payers all over the country the chance to come to the programme.
It takes in people from about a 30 mile radius of wherever we happen to be. On the whole we get about six or seven times as many people applying as we have room for and so we have a very strict application process and then we try to put together as broad a balance as possible.