Around 100 former patients of Jacques Masset accused him of prescribing them sexual acts or encouraging them to partake in orgies or sleep with as many men as possible in order to heal their troubles.
One of his female clients was even told to sleep with ten men a day, while others were ordered to carry out sadomasochistic acts in front of their partners.
Masset, aged 70, went on trial in the French town of Albertville on Wednesday accused with “abusing the weakness individuals with psychological troubles.”
While many of his patients are too ashamed and traumatised to press charges, 17 of his victims are being represented in the case as civil parties.
Masset took advantage of the lack of regulation around psychotherapists and began operating as a therapist in 1990 in the town of Ugine, in the French Alps.
The former cleaner with Annecy council had no qualifications but quickly built up a list of clients and would earn around €10,000 a month, according to reports in the French press.
His method of conning his clients into believing that sexual orgies were they only road to recovery was apparently simple and horribly effective.
His psychoanalysis was always the same: male clients had a sexual problem with their mother and female clients had similar issues with their father.
He would lead them to believe they had probably been sexually abused as children without them realising.
To heal them, Masset would order them to increase their sexual activities, outside of their couple and without protection.
“For some patients it involved torture,” said Roselyne Duvouldy, the lawyer for 14 of his victims. “One of his victims had to sleep with ten men each day,”
To enable his patients to carry out the prescribed therapy he would introduce them to each other.
Masset risks up to five years in prison and a fine of up to €750,000.
A French families charity UNADFI, which helped bring the case against him, said: “He pretended that these orgies, in which he sometimes participated, would prevent them from falling into prostitution.”
“He also brought up false memories of incest for some victims, which had terrible knock-on effects for the families concerned by these false allegations,” said the charity.
According to his lawyer Max Joly, the pseudo-therapist “finds it hard to understand why he is being punished, given that his activity was within the law.”