On Tuesday, around 30 sex workers backed by nine associations, including a medical NGO, went to the Constitutional Council to argue the law infringed their sexual and commercial freedom and made them more vulnerable to attack.
The law, which punishes people caught paying for sex with fines of up to 1,500 euros ($1,800) for first-time offenders and 3,750 euros for repeat offenders, took years to make its way through parliament after fierce debate.
Inspired by Sweden, it makes it a crime to buy sex but not to sell it, shifting the criminal responsibility to clients.
Hailed by many feminist groups at the time as an advance for women's rights, the law was assailed by sex workers as an infringement of “constitutional rights to personal autonomy and sexual freedom, respect of privacy, freedom of contract and freedom to do business.”
The sex workers also argued that by criminalising their clients the law has eroded their earnings, forcing them to take ever greater risks to earn a living.
These include agreeing to engage in unprotected sex or to have sex in isolated environments where they are more vulnerable to attack.
In August a Peruvian transgender sex worker, Vanesa Campos, was killed in the forested Bois de Boulogne park west of Paris. She was shot dead while trying to stop a group of men robbing a client.
“It's the client who dictates his conditions and we have no choice because we have fewer clients than before but still as many bills at the end of the month,” one sex worker, who gave her name as Anais, told AFP after Tuesday's hearing.
Many rights groups argue women do not engage in prostitution freely but are forced to do so by hardship or other circumstances.
They accuse clients of exploiting their vulnerability.
Issuing a robust defence Wednesday of the law, France's High Council for Equality Between Men and Women argued prostitution was “the opposite of sexual liberation” and “oppresses all women” by enshrining the notion of male domination.
The council pointed to a poll showing that 78 percent of French supported the ban as proof of widespread support.
“We don't want a society where it is possible to buy someone else's dignity,” a lawyer for the abolitionist camp, Cedric Uzan-Sarano, argued before the Constitutional Council.
But a lawyer for the sex workers' camp, Patrice Spinosi, countered that by making it a crime to buy sex but not to sell it the state had created a “schizophrenic” situation and “infantilised prostitutes.”
“Who are you to forbid me from doing what I want with my body?” he asked.
The Constitutional Council will publish its decision on whether the law is compatible with France's basic charter on February 1.