Interview: Caroline Lucas MP: the honourable outsider

Her victory had no bearing on the awkward wooing of the following days as David Cameron and Nick Clegg decided whether to climb into bed together. Still, it's hard to overstate the importance of the win, particularly in light of the recent "Green surge" and the rise across Europe of both left and right-wing parties looking to upset their own parliamentary elites.

In that sense Lucas was an outrider, a harbinger of what was to come. She stood down as Green Party leader in 2012, to be replaced by Sydney-born Natalie Bennett, but on the UK-wide platform she remains the most recognisable Green politician.

Up at Westminster for the start of the new term, the first thing Lucas got was an office. The second thing she got was angry - at how out of touch the institution seemed, at how shoddily the business of government was transacted within it, at how poorly it represented the citizenry, at its self-interest and self-importance. And so, five years on, she has written a book about her experiences.

Called Honourable Friends?, it's part essay collection, part parliamentary memoir and entirely a sleeves-rolled-up kind of read. Lucas tackles the creeping privatisation of public services, the hold big business has on government, how parliament can better serve the people, how citizens can (and must) protest, and, of course, about the environmental concerns which are a cornerstone of Green Party policies.

"I think what shocks me so much about Westminster is the absence of real scrutiny," she tells me. "[in a way that is] fundamentally different from any of the institutions I've been part of before."

Among those other institutions are Oxfordshire County Council, where Lucas had her first taste of political office, and the European Parliament, where she served as Green Party MEP for South-East England between 1999 and 2010.

The first was hardly a bastion of enlightened views - Lucas remembers the abuse she got for breast-feeding her three month-old son in the council chambers - but in neither place was she given a pink ribbon on which to hang her ceremonial sword, or told to address colleagues using only arcane honorifics. "I certainly didn't ever think I'd be sitting here looking back to the European Parliament with rose-tinted glasses," she laughs.

Of course the timing of Lucas's book isn't accidental. In a few weeks another game of electoral musical chairs begins and, when the music stops, it'll be not only the Greens but also Ukip and the SNP who expect to have made gains.

According to the most recent constituency poll by Lord Ashcroft, Lucas is 10 points ahead of her Labour challenger in Brighton Pavilion and, though she won't admit it, she can be fairly certain of retaining her seat. When we talk, she has just returned from Norwich South where the Greens hope to pick up a second or possibly even a third MP - Bristol West is another target.

But the book's publication is timely in another way. With last week's cash-for-access "sting" involving Jack Straw and Sir Malcolm Rifkind, the ethical standards of our parliamentarians are once again under scrutiny.

"Sadly it does reinforce the view of many that MPs 'don't get it'," says Lucas of the Rifkind affair. "It's hugely damaging, and further erodes trust in politicians. The work of an MP is about public service, not about getting the highest possible income. A ban on MPs taking on outside consultancy work should be the very least that we demand. If full-time MPs genuinely think they have the time to take on second jobs, I'd suggest they're not giving enough attention to the first one, which should have representing their constituents as the overriding priority."

Lucas didn't have to try too hard to play the outsider when she arrived at Westminster. Keeping hold of that mindset has been trickier, however. She recalls the sisterly advice she received from Labour MP Margaret Beckett in her first weeks in the Commons - "Don't worry, you'll get used to it" - and how she re-tooled it as a mantra about how not to proceed.

"Reminding oneself that not all rules are good rules and sometimes it's good to challenge them is an important part of being an effective parliamentarian," she says. Becoming an insider, getting used to things, is "massively dangerous".

Above the fireplace in her office is a red banner emblazoned with the words, "Well-behaved women seldom make history", a quotation from Pulitzer Prize-winning author Laurel Thatcher Ulrich.

Lucas has clearly made history, so is she the exception to that rule - or has bad behaviour been a vital hallmark of her own political career? Labour's Jimmy Hood (the Honourable Member for Lanark and Hamilton East, to use the parliamentary language Lucas detests) would probably say so. When Lucas spoke at a debate on media sexism in June 2013 wearing a T-shirt bearing the slogan "No More Page Three", Hood told her to cover up.

There aren't many MPs who've been arrested, either. Lucas was, at an anti-fracking demonstration at Balcombe, West Sussex. She was charged with obstructing the highway and later tried and acquitted.

Some, including Labour's Tom Harris, viewed her arrest as a publicity stunt, but Lucas is unrepentant. "It felt like Balcombe really was the frontline at that time," she says. "Given that so many of my constituents were writing to me about it and going there and putting themselves on the front line, it felt like it was all very well me encouraging them but I ought to be putting my body where my mouth was."

Her son Theo, a climate campaigner, was also arrested and while the hand of the law was placed fairly gently on Lucas's shoulder, she says Theo's experience was a little different. "The police went for him first and dragged him out of what was a very peaceful protest and the sight of someone you love being ..." she trails off. "There's a very painful tactic they're using now which is a pinch-point behind your ear and just seeing that happen was excruciating. It was horrible. As he was being pulled away I found myself screaming, 'That's my son'. I didn't mean to say it but it was just a gut, visceral reaction."

Then again, the 54-year-old is no stranger to the frontline. Born into a Conservative-voting family in Malvern in Worcestershire and privately educated, her political awakening came at Exeter University when she discovered CND and became a regular visitor to the Greenham Common and Molesworth Common peace camps.

Then, in 1986, reading Jonathan Porritt's Seeing Green put into "a rigorous whole" many of the issues she was concerned with at the time: feminism, the environment, nuclear weapons. "I still remember the sense of reading that book and feeling that my life had changed," she says. "I literally joined the party on the day I finished the last page."

Thirty years on, Lucas is watching her party transform into a serious player in UK politics. Meanwhile, in Scotland, the Scottish Greens under Patrick Harvie's leadership have established themselves as a Holyrood fixture.

Thanks largely to their role in the Yes campaign, the Scottish Greens have experienced their own version of the "Green surge", with membership jumping to 8,500. Last week they announced that 32 Green Party candidates will stand for election to Westminster in May, with 40% of them women.

Did Lucas agree with the Scottish Greens' stance on independence? "Yes I did," she says, after a slight pause.

There's no hesitation in her praise of Harvie, however. "I think he's a brilliant politician. Seeing him on some of the national debates when he was part of the referendum was so inspiring, and when he does get onto Question Time, Twitter goes mad. Everybody loves him. I think he's a politician with so much charisma and articulacy.

"I would love to see him able to play an even bigger role."

But it isn't all roses for the Green Party. The day after the cash-for-access allegations engulfed Sir Malcolm Rifkind, current leader Natalie Bennett suffered her own horror show courtesy of a radio interview in which she had what she later called "an excruciating mind blank" when asked about a Green Party pledge to build half-a-million new homes.

Lucas and I talk before the gaffe. But if her praise for Bennett isn't to look ill-advised - "I think Natalie's doing a great job," she tells me - then the party had better hope for an improved performance from the Australian should the mooted televised leaders' debates end up including the Greens.

There's a long intake of breath from Lucas when I quote extracts from a recent column in The Economist. The Greens, it said, are "a radical left-wing outfit ... far dottier than UKIP".

Ouch.

"I would say that was pretty lazy, actually," she replies at last. "I think the Greens are posing some of the most important questions of our time, for example how we live sustainably on a planet of finite resources and a rising population, and how do we do that in a way that doesn't exceed environmental limits and which is fair. I don't think The Economist has the answer and it may be that the Greens haven't got every part of the answer right.

"But I believe we're about the only party that's asking that question."

If the numbers are right, more and more people are asking it too.

Honourable Friends? Parliament And The Fight For Change is published on March 12 (Portobello Books, £14.99)