An interesting interview with Caroline Lucas

Whatever you think of the Greens, it would have been hard not to feel that one of the few truly inspiring moments in last week's election came at about 6am on Friday 7 May, when, in a hall on the cold seafront, Green party leader Caroline Lucas was declared MP for Brighton Pavilion, with a 1,200 majority. Jeremy Paxman immediately demanded which side she'd back if there was a coalition (neither, necessarily, she replied politely; she would approach all issues on a case-by-case basis), but an amateur video posted on YouTube gives more of a sense of the enormity of what she achieved for her party of more than 11,000 members, in a first-past-the-post system stacked against them: the camera, dipping and weaving erratically around the room, is trained on the audience as well as the podium. When the results are announced, it catches a supporter wiping away sudden tears.

"It's still sinking in," Lucas says, a week later, settling into a sofa in a friend's house. The South Downs are visible through the front windows; a porcelain Mao guards the fireplace. Lucas, until last week Green MEP for South-East England, has spent the past 10 years in Brussels, renting a room in a house in Brighton, which she has now given up. Her brown-gold suit matches her tawny eyes, and she has a ready smile. It lights up her face before nearly every question, however tricky – making a connection, softening the atmosphere, gaining her a little time. Which is not to say that the arguments, when they come, are soft: she is articulate and forthright, and in a political landscape dominated by an unseemly tussle for the centre, refreshingly different. At one point I mention a common criticism of her party – that it's like a watermelon: green on the outside, red inside. "I love the idea that that's meant to be a criticism. On Question Time the other day David Starkey said, 'Well, the trouble with you is you're socialist.' I mean, 'Yeah. What's your problem?'"

Her first day as MP, the first for any Green in this country, she spent conducting an outdoor surgery; four days later she was in Westminster. Walking in, she felt a confusion of emotions. "It felt a huge privilege and an honour. It felt like this was what the Green party had been working for for over 30 years, and here I am walking over the threshold. It felt archaic and out of touch with reality, it felt historic. It felt like the beginning of school." The new MPs were shown some of the ropes – the coat-hooks, with their pink ribbons on which to hang swords, the chamber, where they were formally inducted, and which was never meant to hold 650 MPs – in fact, it can't, and one of the many things they were told was how to secure a seat on the green benches for a day: turn up for 8am prayers, receive a prayer card, and mark a seat with it. "I mean, what a weird way of allocating things! There are lots of things one can criticise about the European parliament, but it does work pretty well in terms of the speed with which you can vote, the fact that there's room to sit, the fact that there are offices when you arrive" – she, like many new MPs, has no office as yet, and, as the lone Green, no whips' office to help her get one. "I mean, tradition is nice, but we've got to have a workable parliament for the 21st century."

But there will be, as she knows, far greater weirdness, not least the fact that it will be a parliament run by both the Conservatives and Lib Dems. It is a union she feels has in many ways failed before it's begun. "I feel very sad that after all the discussion about the new politics, what it looks like is an awful lot of men in a lot of grey suits doing politics in much the same way. Yes, it's a coalition, and it'll be interesting see how that works out, but in a sense individual parties are a coalition – there's as much between Jon Cruddas on one side and Gordon Brown on the other as there is between Nick Clegg and David Cameron. All parties are coalitions around certain issues. If I were to say what a new politics would look like, it wouldn't be about a referendum on AV" – contempt makes her enunciate even more clearly than usual – "which is one snail-inch, possibly, in the right direction, and not even necessarily that, because AV exaggerates the swings of the bigger parties. It should have been a real moment for political reform."

The introduction of proportional representation for European elections was what took her to Brussels in 1999; she won by 256 votes. If last week's election had been under proportional representation, it might have given the Greens "four or five MPs. But it's a difficult calculation to do, because if there had been PR then more people would have voted Green in the first place, because they'd have known their vote would have counted. You know, all of the expenses scandal, and all of the disillusion with parliament – all of that energy seems to have been wasted. There was such hope that that could have led to some kind of breakthrough in making our parliament more representative, making it more accountable. We could have had more women in politics, we could have had lots of things which could have been about a new politics, which this isn't. This is still going to be about swingeing cuts in public spending, we're still going to be saddled with Trident, and on climate and energy it doesn't sound like there's anything of real ambition."

Another issue is what exactly this sudden elevation on to a national stage will mean for her own party. Lucas, who has been a member since 1986, is often credited with playing a big role in making it electable at all. For much of its 36-year history, as one commentator has put it, the Green party has been "not so much impractical as implausible, immature, frequently impossible and occasionally imbecilic". Deeply suspicious of the possible cult of a single leader, the party had two "principal speakers" – most recently Lucas and Derek Wall. She argued that the public needed a face to attach to the issues and was elected leader in 2008. (And the leadership has to be refought every two years. "If Tony Blair had had to do that," she says, "history would have been very different.")

It was, for the party, a real shift in culture – and further, smaller shifts are being urgently debated as we speak. The party is fiercely democratic: every possible change must be properly debated. Now that there is an MP in the fast-moving world of Westminster, however, this process threatens to become too unwieldy. "We've got meetings happening about how we make structures more workable, but I think the Green party has something really important to offer to the political world – which is about how it is possible to keep your principles around internal democracy and have effective representation."

She is also credited with helping to retool the party's pitch. For anyone who might assume that the Greens are the party of recycling and composting, of teepees and hairshirts, their manifesto – which begins with the economy, moves on to everyday life, citizens and government, and only gets to the environment on page 33 – is something of a surprise.

The Green party is a party of social justice as well as of environmental continence, and it argues that one cannot happen without the other: the manifesto articulates a world in which maximum wages in any corporation can be no higher than 10 times the lowest, the railways will be nationalised and the NHS de-privatised; where most people cycle and ride trains, have decent pensions and are paid a living, as opposed to a minimum wage. Reading it is, in fact, like entering an alternate world, in many ways a very attractive world, if somewhat slow (they would impose a maximum 55mph on motorways), somewhat earnest and obsessed with detail.

But the manifesto also articulates some policies that, if highlighted during the election, would have been red meat to the tabloids: the idea that everyone should eventually receive a citizen's income, for example, whether they are working or not; that heroin should be available to addicts on the NHS; that the needs of refugees should be prioritised over the economy. There was an idea knocking around their spring conference of a kind of NHS for pets – it didn't get into the manifesto, but might well return for further discussion. How is she to sell this kind of proposal in parliament without, frankly, opening herself up to mockery? "It's a question of priorities," she says. "Right now the issues are around the economy, around the Green new deal, around social justice and fairness – and when the time is appropriate, the animal rights stuff as well."

In Lucas the Green party has got a leader – and now an MP – who while reassuringly proper-seeming, and fantastically well-spoken, ticks all the trench-warfare boxes. The daughter of a businessman who owned a central heating company in Malvern and a housewife who raised three children, Lucas grew up in a milieu of unquestioning Conservatism. It was the Falklands war, in 1982, and the nuclear threat, that shattered this complacency; by the time she was studying for an English literature degree at Exeter University she was spending hours on buses, trekking up to Molesworth and to Greenham Common.

Halfway through her PhD in English and women's studies she happened upon Jonathon Porritt's book Seeing Green. "It switched a lightbulb on in my head, [because it] put so many of the concerns that I had, nuclear disarmament or the environment, or women's groups or whatever, into a coherent political whole." It seemed like fate that the Green party HQ was just down the road in south London, so she volunteered. When a job came up, in the press office, "I persuaded them that expertise in 16th-century literary romance was exactly what they needed". Her normalising strategy was apparent even then. "When someone was going to do a TV interview and they looked like the stereotyped Green, what I'd say was, 'You know, dress how you like, but what I want people to be doing is listening to what you're saying, not making comments about anything else.' But that's very different from any kind of compromise on policy."

Having decided she wanted more influence on Green policy, she left the party's employ, and fetched up as a press officer for Oxfam, in Oxford, where she met her husband. They have two children, now 14 and 17, and she admits that it was one of the hardest decisions in her life to stand as an MP, knowing that if she won she would have to uproot them. Unfortunately, she says, "with politics you can't say, 'Well, I'll come back in five years.' Things move on – the circumstances were right for a breakthrough now."

She has been arrested at Faslane, and outside Westminster – "I'd been to Iraq, and met doctors in Basra who were talking about women giving birth to children with deformities. There was a demonstration in London against the use of depleted uranium. There was a moment – I was with Mark Thomas, actually, the comedian – when we both just ran into the road and lay down in front of a police car … It's not something I do lightly – it's not some sort of joke. I think there is a role for non-violent direct action when democratic channels have failed."

Now 49, Lucas has years of experience on local councils and as an MEP, but Westminster is a different beast, and her voice one against hordes. The worry, surely, is that it will get lost, that the wheeling and dealing, the sheer numbers game, will drag her off-course. "I'm very grounded in why I'm there and what the important issues are," she replies. "I passionately hope it is possible to demonstrate that you don't have to get your hands filthy in terms of doing politics."