From the Telegraph:
The curious rule was first introduced in late 1799 by Paris' police chief, and stipulated than any Parisienne wishing to "dress like a man" must seek special permission from the city's main police station.
This makes the laissez-faire French capital theoretically more hardline than Islamic states like Sudan in the fashion stakes.
But a group of ten French MPs has now submitted a draft bill to parliament to remove the law, which has survived repeated attempts to repeal it.
In 1892, it was slightly relaxed thanks to an amendment which said trousers were permitted "as long as the woman is holding the reins of a horse".
Then in 1909, the decree was further watered down when an extra clause was added to allow women in trousers on condition they were "on a bicycle or holding it by the handlebars".
In 1969, amid a global movement towards gender equality, the Paris council asked the city's police chief to bin the decree. His response was: "It is unwise to change texts which foreseen or unforeseen variations in fashion can return to the fore."