A Canadian court has lifted a 12-year-old girl's grounding, overturning her father's punishment for disobeying his orders to stay off the internet, his lawyer said.

The girl had taken her father to Quebec Superior Court after he refused to allow her to go on a school trip for chatting on websites he tried to block, and then posting "inappropriate" pictures of herself online using a friend's computer.

The father's lawyer Kim Beaudoin said the disciplinary measures were for the girl's "own protection" and is appealing the ruling.