By Emma Griffiths
Political reporter, BBC News
Family: Divorced, lives with partner, three children
Education: Grammar school, Broadstairs, Kent
Lives: Carshalton and Hampshire
Career: Marketing/design, founder of Fathers 4 Justice
Standing for political office, it appears, has not diminished Matt O'Connor's reputation as a professional troublemaker.
On his way to our interview, the Fathers 4 Justice founder was stopped by police outside the Houses of Parliament - scene of one of the campaign group's most controversial stunts, when protesters hurled purple flour at Tony Blair in the despatch box.
Apparently Mr O'Connor had been recognised by the officers.
But two years after he announced the group would disband, he has not left the controversies behind him for his mayoral bid.
Launching a poster urging people to "save London from Labour's tartan taxes" in London and Holyrood at the same time certainly got some people's backs up.
It was met with complaints of "race slurs" and Mr O'Connor has confirmed police are looking into one complaint. He shrugs it off as "laughable" and a "sense of humour failure".
He also delivered a symbolic "bath of blood and roses" to City Hall to highlight one of his main campaigning issues - combating teenage violence, or as he puts it "London's bloody harvest of bullets and blades".
Need for fathers
He points the finger at the government's social policies for creating an "epidemic of fatherlessness" and family breakdown, which in turn he says has left "feral" children running amok.
A divorcee himself with two children by his first wife and another with his partner Nadine, he says it is not about forcing people to stay married, or the traditional "nuclear family" but about making sure children retain the love and care of both parents after separation.
"Child support shouldn't just be about financial support or economic support it should be about emotional and financial support - the government doesn't recognise that," he said.
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"I'm concerned very much about family breakdown ... even setting to one side the issues of fathers and family courts ... the human tissues and embryology bill removes the need for fathers by design.
"This government is actually pursuing policies which are trying to make fathers redundant emotionally and biologically. Fathers are seen purely financially - you can abandon your child tomorrow, provided you pay, that's this government's view on fathers."
He says he wants to put "fathers back into families" - he believes gangs are the result of boys deprived of male role models looking to create a new family on the streets.
Born into a Labour-supporting family, Mr O'Connor says he supported the miners' strike as a schoolboy, and was involved in the anti-apartheid movement.
But seven years ago he fell out of love with the Labour Party. He said going through the family courts system was a "baptism by fire" and he says he realised the democratic system was broken.
He has got "no truck" with "professional politicians", referring to the three main mayoral candidates as "Mr Faceless, Mr Clueless and Mr Shameless" and only intends to stand for one term as mayor if he were voted in.
He is surely the only mayoral candidate also planning to launch their own ice cream brand this year - he says it will be a philanthropic venture, with some of the profits going to groups working with London's youngsters.
Mr O'Connor describes himself as a "creative impresario" working on "brand concepts", marketing, design and PR.
Since announcing Fathers 4 Justice - which hit the headlines by members dressing up as superheroes and climbing up Buckingham Palace and other buildings - would disband, he has been writing a book about their exploits.
He had been planning his next strike against the ruling political elite, but the plans for a People's Alliance were put on hold after he was approached by the English Democrats to run for mayor of London.
He said he had been "resistant to the idea of politics because I didn't want to climb the greasy pole" but he said he wanted to break the stranglehold of the three main parties and try "to find a new way forward".
But how does the English Democrats' call for a separate English Parliament chime with his own agenda?
"My agenda is quite clear, I've always approached things from the view of greater democracy, greater rights for people, greater balance and equality."
Fathers 4 Justice stunts often involved superhero-suited protesters
He believes democracy is "bankrupt" with politics tainted by scandal and "incompetence" - all of which, he says, means people despaired of politics.
"For me it was about how can we have a better democracy? Why is it we have a Scottish prime minister who develops policies for England but his policies do not affect his own constituency?
"There is a democratic deficit in this country."
He characterises himself as a "libertarian". He is a critic of the use of the DNA database to hold details of anybody who has been arrested, regardless of whether they are charged, and is not a fan of too many CCTV cameras: "We are creating a nation of suspects, a spy society."
But he does believe in a zero tolerance approach to crime and more community policing, as well as more involvement from church and voluntary groups in helping youngsters.
Unusually he says he would only stand for one term as he has "no desire to become a professional politician" and says one term is enough before you start to "lose touch with reality".
And he is dismissive of current mayor Ken Livingstone's bid to be re-elected for a third term: "Anybody who believes in democracy should, after two terms, stand clear. You've got to let somebody else into the job."
He is strongly against expanding Heathrow, saying the government has displayed "total cowardice", not because of the usual environmental reasons - but because of the danger of a plane coming down over London - instead he would see a new airport built in the Thames estuary, in a similar manner to that built off Hong Kong.
And, as a designer, he would like to see London become an "innovation hub" - attracting the best creative talent in the world. He is no fan of the congestion charge and is among several mayoral candidates who would like to see the Routemaster bus return to London's streets.
He says he has been approached by various parties to join them, most recently the BNP.
'Near the knuckle'
Mr O'Connor puts that down to the English Democrats' use of the St George flag, which he says has become unfairly associated with the far right, "partly because the idea of England was abandoned. I think that needs to be challenged".
"I said I would rather eat my left testicle than join the BNP - bear in mind I was in the anti-apartheid movement," he added.
He says he is "along for the ride" in the mayoral race and says he does not have any expectations .
"If you're a small party let's face it, you've got a serious uphill task," he said.
"It's a bit like Fathers 4 Justice, I'm trying to get people talking about it, start thinking about things then you can create some kind of climate change in terms of whatever issue you're trying to raise a profile of.
"My raison d'etre in this is really about the kids first and the imbalance of the United Kingdom second."
Despite the complaints about his posters, he said he will not be curbing his campaign but will expand the "range and nature" of the ads. He promises a "near the knuckle" campaign. It seems the spirit of Fathers 4 Justice lives on.
"The reality is if I had more money than God, like Boris, I would be running a different campaign," said Mr O'Connor.
"That's what we're up against, give me £1.2m and I'm going to run a campaign in a much different way. Give me 50p and I will give you the best I can do for that amount of money. That is the reality of politics."