THE former IMF boss had no way of knowing he was sleeping with prostitutes during swinger sessions because "the women were all naked at the time", his lawyer has claimed.
The defence came amid allegations his mobile phone records showed he had relationships with 10 call girls.
A host of recent revelations have already established the insatiable sexual appetite of the 62-year old one-time French presidential favourite.
But the new records could help police determine whether the former International Monetary Fund chief was aware that the women he had sex with had been paid to do so.
Sleeping with prostitutes is legal in France if the girls are over 18 but some warn Mr Strauss-Kahn could face charges if the case expands to cover graft or procuring.
The 10 French or Belgian women to whom police traced calls to Mr Strauss-Kahn, all claim to have had paid sex with him while he was IMF chief right up to his arrest last May on charges he tried to rape a New York hotel chambermaid.
But in an intriguing line of defence, Mr Strauss-Kahn's lawyer Henri Leclerc said his client could have been "totally unaware" that the women he met in swinger sessions were prostitutes.
"At these parties, people were not necessarily dressed, and I defy you to tell the difference between a naked prostitute and any other naked woman," he said.
French police are seeking clarify Mr Strauss-Kahn's role as they investigate a prostitute network operating out of a luxury hotel in Lille, northern France called the Carlton.
Some eight leading local figures are under investigation in connection with the Lille network, including the director of the Carlton hotel, a businessman with ties to Mr Strauss-Kahn's party, a police chief and a construction company executive. All deny any wrongdoing.
Several girls allegedly belonging to this network had sex with Mr Strauss-Kahn, even travelling to Washington to do so.
Two girls said together they were paid €1,600 in cash per session by two men under investigation in the Carlton Affair but only one remembers payment being mentioned during these.
Mr Strauss-Kahn admits taking part in orgies arranged by "friends" as part of his "uninhibited sex life", but that "he never paid a centime" and never asked if his partners were being paid.
"I have a horror of prostitutes and pimping," he is quoted as saying.
The former Socialist politician, who at one point was tipped to be the next French president, has asked to speak to investigators in the case to try to end the "dangerous and malicious insinuations". Le Point magazine claimed police may question him in custody in the coming weeks.
The mobile linking Mr Strauss-Kahn to the 10 girls belonged to Fabrice Paszkowski, a Lille-based businessman currently under investigation for "aggravated procuring by an organised group".
Mr Paszkowski mislaid it during an encounter involving Mr Strauss-Kahn and four women in a luxury Paris hotel in February last year.
DSK, as the French call him, later allegedly retrieved the phone, using it to contact his friend and arrange meetings with girls for the three months leading up to his arrest in May on suspicion of trying to rape maid Nafissatou Diallo.
When charges were dropped, he returned to France only to face separate allegations that he tried to rape a young writer eight years ago.
These too were dropped and Mr Strauss-Kahn has been tentatively seeking to return to public life, making recent appearances at an economic forum in China and in Sarcelles, the Paris suburb where he was mayor.
But his bounce back efforts have been hampered by a string of testimonies from escort girls alleging they had sex with him. Some claim he was "brutal" but none have pressed for charges