Paris, Oct. 14: More than a year after resigning in disgrace as the managing director of the International Monetary Fund, Dominique Strauss-Kahn is seeking redemption with a new consulting company, the lecture circuit and a uniquely French legal defence to settle a criminal inquiry that exposed his hidden life as a libertine.

Strauss-Kahn, 63, a silver-haired economist, is seeking to throw out criminal charges in an inquiry into ties to a prostitution ring in northern France with the legal argument that the authorities are unfairly trying to “criminalise lust”.

That defence and the investigation, which is facing a critical judicial hearing in late November, have offered a keyhole view into a clandestine practice in certain powerful circles of French society: secret soirees with lawyers, judges, police officials, journalists and musicians that start with a fine meal and end with naked guests and public sex with multiple partners.

In France, “libertinage” has a long history in the culture, dating from a 16th-century religious sect of libertines. But the most perplexing question in the Strauss-Kahn affair is how a career politician with ambition to lead one of Europe’s most powerful nations was blinded to the possibility that his zest for sex parties could present a liability, or risk blackmail.

The exclusive orgies called “parties fines” — lavish champagne affairs costing around $13,000 each — were organised as a roving international circuit from Paris to Washington by businessmen seeking to ingratiate themselves with Strauss-Kahn.

Some of that money, according to a lawyer for the main host, ultimately paid for prostitutes because of a shortage of women at the mixed soirees orchestrated largely for the benefit of Strauss-Kahn, who sometimes sought sex with three or four women.

On Thursday, Strauss-Kahn broke a long silence to acknowledge that perhaps his double life as an unrestrained libertine was a little outré.

“I long thought that I could lead my life as I wanted,” he said in an interview with the French magazine Le Point. “And that includes free behaviour between consenting adults. There are numerous parties that exist like this in Paris, and you would be surprised to encounter certain people. I was naïve.”

“I was too out of step with French society,” he added. “I was wrong.”

This month Strauss-Kahn won a significant legal battle after a French prosecutor dropped part of the investigation into an alleged sexual assault at a hotel in Washington. A Belgian prostitute recanted her earlier accusation, saying the encounter was just rough sex play, but Strauss-Khan is still a suspect for involvement in a prostitution ring.

Buoyed by that first victory, Strauss-Kahn’s lawyers predict he will triumph in France, where having sex with prostitutes is not illegal, although soliciting and pimping are.

In essence, they argue, there is nothing criminal about the sexual life of a libertine, according to Strauss-Kahn’s lead lawyer, Henri Leclerc.

That defence may not satisfy the charges in a New York civil lawsuit filed by Nafissatou Diallo, who accused Strauss-Kahn of sexual assault last year in a New York hotel where she was a chambermaid.

Strauss-Kahn’s name first surfaced in the French inquiry by chance, in May 2011. French investigators were tapping the telephones of Dominique Alderweireld, an owner of Belgian sex clubs who is also a suspect in the prostitution ring.

In one conversation between Alderweireld and a long-time childhood friend, René Kojfer, who worked at the Carlton Hotel in Lille, the men were gossiping about Strauss-Kahn’s recent New York arrest, according to lawyers involved in the case.

They then recalled a freewheeling luncheon in 2009 at a Paris restaurant called L’Aventure, and Kojfer discussed whether they could make money by offering information about that day to Diallo’s lawyer, Thompson, who was never called, the lawyers said.

At L’Aventure, Strauss-Kahn and a few friends gathered in a private basement club, carpeted in purple and black tiger stripes, with a female Belgian escort and Alderweireld’s companion, Béatrice Legrain, who recalled that lunch in an interview.

She said that Strauss-Kahn, energised by Viagra, had sex with the escort and then followed Legrain to the bathroom, grabbing her and demanding sex. But she said she rebuffed him and it “wasn’t a big deal”.

Alderweireld made light of the “petit” episode at L’Aventure. His lawyer, Sorin Margulis, took a more scornful view: “It’s more an act of Louis XIV.”

The investigation into the prostitution ring in Lille ultimately swept up 10 suspects, including Strauss-Kahn.

They knew each other largely through their membership as French Freemasons, according to Karl Vandamme, a defence lawyer who represents Fabrice Paszkowski, who played a crucial role in organising the sex parties.

The banker, Vandamme said, would typically arrive late for the more than a dozen parties, held over a period of about five years. There was a rhythm to the gatherings, with everyone dressed for a sit-down dinner, he said.

Then over time, couples separated, “kisses were exchanged between one woman and another and between a husband and the wife of a friend” until the guests “all ended up nude”.

Hubert Delarue, the lawyer for Kojfer, predicted that most of the suspects would be cleared. Strauss-Kahn’s lawyers argue that he was unaware that some of the women were prostitutes because they were all naked by the time he arrived late.

Delarue said: “Today…, there are occasional prostitutes, and sometimes they’re top models who try to make ends meet.”