A man will now have to spend three months in jail after his hands landed him in trouble while on a crowded bus in Paris, France.
The court heard that the visibly drunk man smacked a young lady on the buttocks and made an insulting comment about her breasts.
The woman managed to alert the driver who locked the bus doors until the police arrived and arrested the man.
A judge in Evry, south of Paris, sentenced the man, in his 30s, to three months behind bars for the slap, considered an act of outright sexual aggression, and added a fine of 300 euros for the offending comments.
Court and justice ministry officials said the fine was the first imposed under legislation that seeks to deter predatory remarks and harassing actions such as wolf-whistles, which are fairly commonplace in public life in France.