It is nearly two years since the expenses scandal broke but the damage it did to our politics remains.
The reputations of MPs and Parliament are still tarnished.
That's because the problems at the heart of our politics go deeper than expenses.
Cash for honours.
Cash for questions.
Former cabinet ministers for hire.
Family members paid £40,000 a year to do nothing.
For years now, huge numbers of people have chosen not to vote because they think it doesn't matter. They think their voice will be ignored.
Who can blame them?
For years, politicians and parties have courted the votes of a few thousand people in marginal seats and ignored the rest.
For years, MPs with jobs for life have put their feet up and taken you for granted.
For years, single parties formed governments when barely a quarter of the people voted for them.
No wonder people have given up caring.
No wonder confidence in politics is so low.
No wonder people are so ready to believe the worst about their politicians.
Westminster is often referred to as the mother of all parliaments.
Our democracy should be a shining beacon to people across the world.
It should be something we can be proud of. Yet, so often, it is not.
There is no single way to solve our problems. They can't all be fixed over night. But there are changes we can make.
We can give people the right to sack corrupt MPs.
We can stop MPs speculating on the property market with your money.
We can bring democracy to the House of Lords.
We can make sure every vote is worth the same.
And we can change the way we vote so that no one's vote is wasted and MPs are forced to work harder to win and keep your support.
We have a chance to do that this May when the Fairer Votes referendum takes place.
What's wrong with First Past the Post?
The choice in May is between two ways of voting, the First Past the Post system we use now and a new way, the Alternative Vote or AV.
It is no secret that the Prime Minister and I come at this from different directions.
What we do agree on is that the people know best.
We both want as many people as possible to get involved and make their feelings known at the ballot box.
And what we are clear about is that this referendum is not about the Coalition Government.
Whatever the result we will continue to work together in the national interest.
Before I talk about why I believe the Alternative Vote is a fairer system I want to talk briefly about the one we have now.
First Past the Post was perfect for a time when the choice was only ever between two parties.
But that hasn't been the case for a long time, not only because of the Liberal Democrats but other parties too - the SNP in Scotland, Plaid Cymru in Wales, the Green Party and UKIP.
Politics has changed and it has changed for the better.
It is more reflective of the broad range of opinions in British society.
In 1951 the two old parties shared 97 per cent of the vote.
In 2010 they couldn't muster two thirds.
Research has found that the result of the last election was decided by fewer than 500,000 votes.
That's out of nearly 40 million eligible voters.
And last year more than two-thirds of MPs were elected with fewer than half the voters in their constituencies choosing them.
That means most of us are represented by an MP that most of us did not vote for.
Where is the democracy in that?
Where is the legitimacy in that?
What was fit for the 1950s is not fit for the 21st century.
First Past the Post leads to a whole host of problems.
It makes politicians more concerned with getting their own supporters out than to appealing to anyone else.
It means that MPs can go about their business without ever having to appeal to the majority of their constituents.
Surely we can all agree that MPs should work hard for your vote.
Yet increasingly First Past the Post makes it easy for MPs to ignore you altogether.
Under First Past the Post, there are huge numbers of MPs with jobs for life in places where one party wins election after election and no one else stands a chance.
If you live in one of these places and you don't support that party, what are you supposed to do?
You either vote, knowing deep down your vote is wasted, or you just don't even bother.
It is because there are so many MPs with jobs for life that there are so many who can take their constituents for granted.
And it is because there were so many MPs taking their constituents for granted that so many abused their expenses.
There was a clear link between how safe an MP's seat was and how likely they were to abuse the system.
When a person is corrupt they should be punished.
When a system makes corruption more likely it should be changed.
So no, First Past the Post is not working.
It is out of date and it is at the heart of so many of the reasons that people don't engage in or care about politics.
It means most MPs are elected without the support of most of the people they are supposed to represent.
It means millions of votes make no difference whatsoever.
It means millions of voices going unheard.
First Past the Post is not working and it's time to do something better.
Why AV is better
Under the Alternative Vote, politicians will need to aim to get half of their constituents to choose them.
That means they will have to work harder to appeal to more people than before.
It means they will have to reach out to people who were ignored under First Past the Post.
It means they will no longer be able to rely on just their core supporters and ignore everyone else.
They will be more legitimate and will carry a stronger mandate from a broader range of people.
That can only be good for our democracy.
Under the Alternative Vote, there will be fewer MPs with jobs for life in safe seats.
That means people whose voices have been ignored will be listened to again.
It means that parties will have to compete for votes in every corner of the country and not just those few marginal seats.
It means more people get listened to and more respect for the different opinions and feelings we share as a nation.
That can only be good for our democracy.
Under the Alternative Vote, there need never be another wasted vote.
That means you can use your vote positively.
It means you can feel confident voting for the person or party you want to win and not have to think tactically about who can win.
That can only be good for our democracy.
The Alternative Vote puts you back in charge.
You get a bigger say in who your MP is. A bigger foothold in our democracy. A bigger stake in our country.
And that will mean more people getting interested and involved in politics, knowing that their voices will be heard and that their actions can have a real impact.
And that can only be good for our democracy.
The Alternative Vote is a simple change that will make a huge difference. It means MPs working harder, more voices being heard and power put back where it belongs - with you.
Taking on critics
Opponents of AV say it is too complicated.
In fact it's really simple.
It's as easy as 1-2-3.
All you do is put a number one next to the person or party you want to win.
You put a number two next to your second favourite and a three next to your third favourite.
And if you only want to vote for one person then you can.
They use a form of AV in Australia and we use it to elect the Mayor of London.
It's not too complicated for Australians or Londoners.
This is not some strange, complex system. It's simple and it's fairer.
Opponents of AV say it is somehow against British tradition.
The beauty of the Alternative Vote is that it is evolution not revolution.
It's a small change which will make a big difference.
It not only keeps the link between MPs and their constituents, it strengthens it.
Opponents of AV say that it will produce unstable governments.
This could not be further from the truth.
The Alternative Vote can and will produce strong, stable governments.
Research looking at every election since 1983 shows that if AV had been used the same party would have won and formed a Government, if with a different majority. But all MPs will have had to work harder for your vote.
The only election that would have resulted in a hung parliament was last year's, just as it did under First Past the Post.
Australia has had AV for 80 years and they've had fewer hung parliaments than we have with First Past the Post.
Do you remember how it felt when you heard about MPs spending your money on duck houses and having their moat cleaned?
Do you live somewhere where the same party wins every time and you feel powerless?
Do you ever look at politicians and parties and think these people don't care about me?
That's what this is about.
We deserve something different.
We deserve something better.
We deserve a new way of doing things.
First Past the Post doesn't work any more.
It leaves too many voices unheard.
It leaves too many people powerless.
It is at the heart of why so many people don't vote.
The Alternative vote is better, fairer.
It puts you back in charge and makes MPs work harder for your vote.
When we have the chance to clean up politics and make our democracy better we should take it.
We have the opportunity to do that in May by voting Yes to Fairer Votes.