LILLE - The judge who has placed Dominique Strauss-Kahn under investigation for "aggravated pimping as part of an organized gang" is a woman, like the large majority of young magistrates in France. An attractive 37-year-old brunette with dark eyes, Stéphanie Ausbart is married and "a very hard-worker," according to all the lawyers who work with her. She is also described as a "stubborn."

The credentials and reputedly "incorruptible" character of the magistrate is one more factor stacked up against the former International Monetary Fund chief, whose U.S. lawyers are struggling to get him freed from a civil suit stemming from the encounter last year where a New York hotel maid said DSK sexually assaulted her.

But at the same time, after criminal charges in the New York case were dropped, Strauss-Kahn has wound up at the center of a criminal probe into an alleged high-end prostitution ring in Lille, a mid-sized city north of Paris. That's where he has faced off in front of Ausbart, who has been presiding over the case for months.

During the last year, Ausbart has been questioning witnesses, suspects and other parties in her office on the 10^th floor of the Lille courthouse. Those who have met her say they quickly realize that this judge knows her material, and is as tough as nails. When René Kojfer, public relations manager at the Carlton Hotel, pleaded ingenuousness in his lispy voice, Ausbart stood up and, drumming her fingers on the table, made it very clear that she expects to be taken seriously.

The courtroom tears from David Roquet, one of DSK's party organizers, did not impress her either. She allowed him to dry his eyes and then continued with her next question: "Could it not be thought that if this important politician had not been taken for questioning in the United States on rape charges, you would no doubt have continued your activities?"

And she seems almost mocking when she mentions the "competition" among members of DSK's entourage to please their high-placed friend. Strauss-Kahn vehemently denies the charges, which he says are part of a concerted effort to discredit him.

The judge has also come up against obstacles on several occasions, notably with the Prosecutor"s Office in Lille. When Police Chief Jean-Christophe Lagarde was placed under investigation for "aggravated pimping," the prosecutor refused to approve temporary detention. Ausbart referred the case to the judge in charge of determining the detention and release of suspects but without success.

Equal before the law

She believes that the members of the gang are all equals and none of the famous suspects should be spared, according to Franck Berton, one of the lawyers on the case. The Prosecutor's Office wanted to take her off the case, but she refused. The Cour de Cassation, (France's court of last resort), supported Ausbart.

In a case where sex and money are the issues at hand, no questions are off limits for Ausbart. "Generally speaking, what were your sexual practices?" she asked one of the suspects under examination. When addressing another she considers a "black thong" found in a bag, and a third suspect is asked "Insofar as you possess a copy of a pornographic magazine as well as a DVD entitled "Nail the coffin", could you explain to us the level of violence of your sexual games? Did you not fear that your children might come across them one evening?" Judging these questions "inappropriate and leading," Roquet's lawyer Eric Dupond-Moretti showed an "extremely worrying puritan streak."

The judge's love of law and order can be traced back to her education. At 24, the young woman from Picardy in the north of France passed the national exams for the Ecole Nationale de la Magistrature (French National School for the Judiciary). In 2000, she was appointed deputy public prosecutor at Senlis, just north of Paris, before joining the court at Mont-de-Marsan in southwest France from 2003 to 2007. She then became a judge at Dax, also in the southwest, before being appointed to the Instruction, a French legal term which refers to an independent group of magistrates who examine cases, at Lille in June 2009.

The cases she had previously dealt were mostly common law affairs: incest, fatal road accidents, medical errors. That was, of course, until this case of hotel prostitution was referred to her, and quickly became a national affair indeed. As well as the sexy rendezvous at the Carlton Hotel in Lille, she discovered "libertine" nights taking place in Paris, Washington and Brussels, which DSK would attend.

Read more from Le Monde in French.

Photo - Tours59/World Trade Organization