LILLE, France — There was testimony about lavish sex parties with high-flying power brokers and prostitutes. There were questions about whether certain sex acts were entirely consensual, and the finer points of libertinage. For good measure, topless protesters threw themselves at the car carrying the chief defendant, a man once expected to be president of France, Dominique Strauss-Kahn.

Yet the burlesque-like atmosphere at his trial, and that of 13 others accused of pimping and abetting prostitution, in the northern city of Lille on Tuesday was perhaps topped only by the silver-haired Mr. Strauss-Kahn’s defense: Lust is no crime.

“When you read the criminal complaint, you get the impression it was this unbridled activity,” Mr. Strauss-Kahn told the court, “but it was four times a year.” The rest of the time, he was too busy trying to save the global economy as head of the International Monetary Fund, he said.

In any case, his lawyers argued publicly before the trial, everyone looks the same without clothes, and who can really tell the difference between a prostitute and a naked socialite at an orgy?