A tale of sex and money will unfold in a court in Geneva tomorrow when a would-be artist stands trial for shooting dead her lover, a billionaire banker from the French Establishment.

After four years of investigation, little remains secret about the night that Cécile Brossard, 40, a one-time assistant at an airport boutique in Paris, fired four bullets into Edouard Stern, 50, the scion of an established banking family, as they enjoyed a bout of sado-masochistic sex.

The discovery of Stern’s body, encased head-to-toe in a latex suit, in his Geneva penthouse shook Europe’s financial world in March 2004. Stern’s reputation as a ruthless operator fed theories that he had been silenced by the Russian Mafia, business associates or even secret agents. Within two weeks, though, the confession of Ms Brossard exposed a story of a tortured three-year relationship.

The Stern family and prosecutors initially set out to prove that Ms Brossard, an uneducated woman who had worked as a call-girl, planned the killing for financial gain.

Last February, judges accepted Ms Brossard’s version and reduced the charges from premeditated murder to unpremeditated killing, which carries a maximum sentence of ten years. The arrangement means that the trial will not probe into the divorced banker’s lurid secret life, Swiss commentators say.

Lawyers for Ms Brossard agree with those of Stern’s two adult sons that the relationship was passionate, tumultuous and full of emotional blackmail. Ms Brossard told the investigating judge that on the night of the killing she felt “an explosion in my head” after Stern allegedly taunted her over a million dollars that he had given her. He had won a bank order freezing her account and was trying to take back the money.

Ms Brossard went to a drawer where Stern, a shooting enthusiast, kept three handguns, she said.

“I pointed my weapon at his face and fired the first shot,” she told the investigating judge. “The weapon must have been six inches from his face. I think I hit him between the eyes . . . He got up, turned halfway round on himself and fell. I fired another round at his head.”

Stern had led Ms Brossard on “a sort of mortal tango”, one of her lawyers said. They will cite opinion from a court psychiatrist who found that her action was motivated by love and fear of abandonment rather than desire for financial gain. The Stern family will depict her as a manipulator who toyed with a dependant lover while living with her permanent partner, a Swiss herbal medicine therapist.

Ms Brossard, who has made at least one suicide attempt, is said to be in a fragile mental condition, talking as though her lover was still alive.

The verdict and sentence is unlikely to silence the wilder rumours about the involvement of political-financial circles in the killing, which has inspired two books and numerous magazine articles. If given a light sentence, Ms Brossard could be released as early as next year, according to the Swiss media.

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