The Swedish Pirate Party said the country's government is sanctioning blackmail by making it possible for copyright holders to get people's IP addresses.
"It threatens Swedish rule of law. It's up to the police to investigate citizens, not private interests," said party head Rickard Falkvinge.
He sees a scenario in which copyright holders threaten to file a suit, and collect damages without ever going to court.
"The ministers want it to seem like it's nothing special, but it is," said Falkvinge.
The row started Friday with an opinion piece in Swedish newspaper Svenska Dagbladet. In the article Culture Minister Lena Adelsohn Liljeroth and Minister of Justice Beatrice Ask said that in the second quarter they will move forward with a law that will force ISPs (Internet service providers) to turn over IP addresses.
Copyright holders, however, will first have to produce evidence to support charges of illegal downloading, then a court will decide if IP (Internet Protocol) addresses should be turned over.
But the pair also axed the possibility for ISPs to shut down Internet access for users who illegally download music, films and TV shows.
They also add that the industry will have to offer legal alternatives for downloading, otherwise it will be impossible to defend old business models. Online music services in Europe do not offer as broad an array of content as they do in the U.S.
ISPs seem to support the move. Broadband operator Bredbandsbolaget said it was expected.
"It's good that we don't have to act as the police," said its CEO, Marcus Nylen, in a statement.
But he isn't completely convinced. "It remains to be seen how it will work in practice, and how the law will protect the rights of our users," Nylen said.
This is the second time this year that file sharing has been making head lines in Sweden.
In January Swedish prosecutor Hakan Roswall filed charges against four people for involvement in running The Pirate Bay, one of the most widely used BitTorrent trackers for illegally distributed music, movies and software.
