The case, known as the "Carlton Affair" after one of the swish hotels in Lille where local businessmen and police officials organised sex parties, has seen high-profile personalities, pimps and prostitutes at the bar or in the witness box.
None of the accused is higher-profile than Strauss Kahn, who lost his place at the IMF in a separate sex scandal that also put paid to his hopes of being the Socialist Party's candidate for French president.
But it looks likely that Strauss-Kahn will avoid a conviction as even the prosecutor in the case has called for him to be acquitted, saying there was insufficient proof he had been at the heart of a prostitution ring.
At his trial in February, Strauss-Kahn calmly fended off the accusations, saying that while he was a libertine who enjoyed group sex, he was unaware any of the woman attending the soirées had been paid to be there.
Former prostitutes recounted brutal scenes in which he sodomised them, allegedly without their permission.
The former IMF boss found himself in the dock alongside 13 others including a senior police officer and brothel owner Dominique Alderwired, nicknamed known as "Dodo la Saumure" in a play on words on the French slang for pimp.
Alderwired admits providing prostitutes to friends of Strauss-Kahn, who are among the accused.
They testified to keeping the women's occupation a secret as they sought to impress the "future president of the republic".
While prostitution in itself is legal in France, encouraging and organising its practice is considered to be procuring and is punishable by up to 10 years in prison.