In a speech at the Institute for Government this evening, the Brighton Pavilion MP will say that the system in Westminster is set up "for the convenience of the power brokers".

She will also argue that the UK parliamentary system is itself a barrier to a wider range of voices being heard. Caroline will say:

"If the Greens were to stand candidates in every seat in Britain, it would mean spending over three hundred thousand pounds just in deposits.

"That's more than we'd have to spend on the entire campaign. And the question of how much you'd get back in saved deposits is not very relevant if you have no money left over for leaflets, posters or broadcasts".

In fact, she says that "the odds are stacked against small parties and independent candidates. And it's not in the interests of any of the main parties to change this".

Inefficient

In her speech, the MP will say that, compared to many Parliaments, Westminster is "monumentally inefficient" - but that this too serves the interests of the main parties:

"The reality is that Parliament is this way for a reason: it keeps power in the hands of the whips and the leaders of the main parties.

"They don't want smaller parties or their own more independently-minded MPs to make full use of the powers of the institution, whether to legislate or scrutinise the government.

"One example of this is the lack of explanatory paragraphs for clauses and amendments. This may seem like a small, technical point, but in reality, it means that MPs often have no idea what they are voting on.

"And with the amount of legislation which is now being pushed through means that there is a severe democratic deficit. This is law making on the hoof".

Women in the minority

Caroline will also reflect on the fact that men outnumber women by five to one in parliament and claims that this "undermines the quality of law-making and scrutiny" and that " a mix of ignorance of the problem and self-interest affect issues such as equal pay, rights for temporary and part-time workers, and funding for rape crisis and domestic violence centres".

Power of one

Yet, Caroline will say in today's speech, there are some advantaged to being the lone representative of your party in the Commons, where she does "have a lot of freedom to submit my own amendments, some of which have been supported by other parties".

Lucas also argues that with a coalition in government, it becomes even more important to have independent voices in Parliament:

"On so many issues, from setting up Academies to bringing in the private sector to run the NHS, the three main parties all line up on one side.

"So it falls to the Greens to make the alternative case. That is what we are doing, on climate change, fuel poverty, and a steady state economy, and on Afghanistan, electoral reform, public sector pensions, and many other vital issues".

Change

Caroline is a passionate advocate for parliamentary reform and with spending cuts beginning to bite, she argues that the need for change is becoming more pressing:

"Just queuing up to vote, for example, accounts for around £30,000 a week in MPs' total salary costs. In the last Parliament there were over 1200 votes.

"Since it takes about 15 minutes per vote, that means an MP with an 85 per cent voting record would have spent over 250 hours queuing to vote over the course of the Parliament".

What needs to be protected

Caroline will conclude her speech with her assessment of what should be valued and protected.

She lists the first of these as "a skilled and impartial civil service" , although she adds that the principle of impartiality is "under direct attack".

Pointing to the practice of individuals moving in and out of the civil service, taking jobs in industry and secondments in other sectors and organisations, Lucas asks: "So to whom do these modern civil servants owe their loyalty? The Crown? Their department? Or to their former or future employers?".

The MP also feels that the wider public service "is being undermined from above". She questions the support of the main political parties for private sector involvement in the delivery of public services saying:

"All three parties believe that the private sector should have a significant role in the delivery of public services, and that competition, financial incentives and the profit motive are the most effective spurs for greater efficiency. I think they're wrong".

Welcome

Looking ahead to today's speech at the Institute, Director Lord [Andrew] Adonis said:

"As the only Green in Parliament, Caroline Lucas has a unique perspective on life in the corridors of Westminster.

"Her ideas for building democratic accountability and reforming what are often cumbersome and archaic processes are bold and refreshing. I'm glad to be welcoming her to the Institute for what promises to be a fascinating event".

Ends

Notes to editors

Caroline Lucas appears tonight at 6pm at the Institute for Government: The Power of One: Making an Impact as the Only Green MP.

The IFG will be live tweeting tonight's event @ifgevents #greenmp

A full transcript of the speech will be available after the event at http://www.instituteforgovernment.org.uk/

About the Institute for Government

The Institute for Government is an independent charity with cross-party and Whitehall governance working to increase government effectiveness.