Fraud prosecutor and green crusader beats favourite Nicolas Hulot in Greens-Europe-Ecology primary race

Eva Joly, the ruthless fraud prosecutor who nailed the 1990s corruption scandal at oil company Elf, is to run for French president.

Joly stunned France by winning the primary race for France's new expanded environmental party, Greens-Europe-Ecology, beating the favourite, TV presenter Nicolas Hulot, with 58% of the vote against Hulot's 41%.

Her score was seen as a victory for her theory of "combative" environmentalism. She has promised to attack lobby groups and financial interests and suggested creating an international court for crimes against the environment. She is a fierce advocate of pulling France out of its dependency on nuclear power.

The maverick 67-year-old with trademark red glasses is a household name in France. Her pursuit of corruption at the highest reaches of the French elite inspired film director Claude Chabrol's dark thriller A Comedy of Power, where Isabelle Huppert played a vengeful magistrate loosely modelled on Joly.

Joly on Tuesday announced: "Ethics is possible, even at the head of state," vowing an end to the corruption scandals still gripping France.

Born in a working-class suburb in Norway, she came to Paris as a young au pair to finance her legal studies and ended up marrying the son of the bourgeois family she was posted to, despite their disapproval. She now holds joint Norwegian-French nationality and will be the first dual national to run for the French presidency – a fact she uses in her attacks on the anti-immigration extreme-right. She vowed to be the "candidate of mixed blood" and "a France which doesn't accept discrimination or ghettos".

Joly's Norwegian accent and monotone voice is seen by some as a severe handicap. But she staunchly refuses to take coaching in communications. Indeed, pollsters feel her no-nonsense approach and lack of TV style plays well to a French electorate fed up with spin.

Joly is a relative newcomer to politics. She was elected MEP for the Paris region in 2009, before her party Europe Ecology merged with the old Green party, Les Verts, to create a new green movement known by the initials EELV.

Membership has soared after good turnouts in regional and local elections. Joly has anchored herself firmly on the left, but she must now come up with a social and economic programme that can convince voters beyond environmental issues and her trademark crusades against high-level corruption.

The Greens hope to boost their score to around 10% in the presidential election. Joly is currently personally scoring around 6% in polls.

Some key EELV figures, such as Daniel Cohn-Bendit, the MEP and former student leader of May 1968, who supports Joly, have worried about the rise of the extreme right's Marine Le Pen. Cohn-Bendit has warned the Green party should consider ditching its candidate and rallying behind a Socialist party candidate in order to avoid splitting the leftist vote. If the left vote is split, Le Pen could get through to the presidential second round.

The EELV party will also position itself as potential future parliamentary allies of the Socialist party if a Socialist wins the presidency. This could see Joly appointed as a minister in a Socialist government.

(Published by The Guardian - July 12, 2011)