This has been the saddest fortnight since I entered Parliament nearly a decade ago. Voters have rightly been appalled by the steady stream of revelations about MPs' expenses.

Over the past weeks, I have questioned my decision to come into politics. In conversations with constituents, friends, neighbours, the subject is the same: the abuse of the Westminster expenses system. The verdict on the streets of Tottenham is unequivocal: Parliament stinks.

People feel hugely disappointed in the behaviour of too many MPs. Party members - who have trudged the streets knocking on doors year-in year-out, donated their hard-earned cash, given up weekends to staff party stalls - feel let down. They cannot understand how some of those elected to serve can have engaged in systematic abuse for what appears to be personal gain.

My constituents are dealing with the most painful economic hardship for a generation. The threat of redundancy and the fear of repossession hang over many. In Northumberland Park ward, people face the highest rate of unemployment in London. Those in employment are working long hours to support their families - office cleaners going to work in the early hours of the morning, security guards working through the night and over the weekend, others working two or three jobs to make ends meet.

Labour must be the party of hard working families, standing up for the values of fairness and social justice. How can we reconcile these values - and the battles that working men and women have fought throughout our history - with some of the revelations of the past few weeks?

The current expenses system - which I have used like all MPs - is deeply out of touch with voters and their daily lives. The entire system must be overhauled. Parliamentarians who have abused the system and broken the rules must go, and the offices of Parliament must be renewed with a new moral authority.

But we cannot stop there.

When I arrived in Parliament in 2000, I said in my maiden speech that Tottenham had felt a long way from Westminster. Some important changes have been made to Parliament since 1997 - more family-friendly hours of business, more women MPs, a chamber that better represents the ethnic diversity of Britain today.

But these reforms haven't gone far enough. The rules have changed, but the culture of Westminster hasn't. For the vast majority of voters who don't have moats to clear or chandeliers to install, it's not the upper class they are indignant at - it's the political class. They feel excluded and failed by professional politicians schooled in and around Parliament but with little empathy for the people beyond the Westminster village.

The vast majority of MPs go into politics to serve the public; they don't do it for personal gain. But the failure to reform the system of expenses has made politicians complacent. Too many have become detached from the everyday expectations of voters - and some have behaved as if the rules don't apply to them.

For Labour, the message is clear. We must never become the Establishment. We must never be satisfied that the job of modernising Parliament - of ensuring that our political institutions reflect and represent the realities of daily life - is complete.

Our collective failure to right the wrongs of the system has been manipulated by those who sneer at the notion that politics has the potential to transform lives for better. Behind their rhetoric lies a loathing for the achievements of the past 12 years - and an anti-politics that neatly complements the agenda of our political opponents.

Labour MPs go to Westminster to serve. We must never allow ourselves to be directed away from that, by our opponents or by our own failure to act boldly.

We have to acknowledge that the only way to truly reform Parliament is to change the way that people are chosen - and to change the people who go there.

Here lies an opportunity to rebuild the bridges between Parliament and the people. We cannot have trial by media. But the worst transgressors must face deselection. In their place, constituency parties should have the freedom to choose local candidates - such as nurses, teachers, and self-employed people - who understand and reflect the anger now directed against the political class that has failed them.

We should look again at the way we select candidates. Introducing primaries in which supporters could vote alongside party members would engage local people and would boost the prospects of candidates rooted in the constituency.

Parliament must respond with vigour. The consequences of failing to do so were all too clear to me as I delivered leaflets in Barking last week. We now face the prospect of the BNP winning seats in the European Parliament. That would have real consequences at home and for Britain's place in the world. Just as the United States is coming to terms with its own complex multiethnic heritage, Britain could be moving in the opposite direction. We must act decisively to stop that at all costs.

David Lammy is MP for Tottenham and Minister of State for Higher
Education and Intellectual Property