A French senator has been questioned on suspicion of plying an MP with a drug without her knowing, reports BBC News.
Joël Guerriau was detained at his home after the MP allegedly had a drink with him and then complained of feeling unwell.
She was taken to hospital where samples are said to have revealed traces of the drug ecstasy in her system.
As a result of the tests she then filed a criminal complaint.
On Friday, police in Paris questioned the 66-year-old senator on suspicion of "administering to a person without their knowledge, a substance likely to diminish their judgement or self-control, to commit a rape or sexual assault".
Mr Guerriau is one of 18 independents in the French upper house and a member of the centrist Horizons party.
While he was in custody he was also challenged by the MP who gave her account of what happened, French reports said. Her lawyer said the MP was still in a state of shock.
Julia Minkowski told AFP news agency the two politicians had known each other for about 10 years and spoke of the MP's "feeling of betrayal and total incomprehension".