Under the new legislation, social media companies have 24 hours to remove posts that obviously violate German law and have been reported by other users. In cases that are more ambiguous, Facebook and other sites have seven days to deal with the offending post. If they don't comply with the new legislation, the companies could face a fine of up to 50 million euros ($57.1 million).

The law was passed with votes from the Christian Democratic Union (CDU) - Social Democratic Party (SPD) government coalition. The Left Party in the Bundestag voted against it, while members of the Greens abstained.

The new rules are supposed to drastically reduce the number of posts containing hate speech, fake news and terror propaganda on social media. In January and February 2017, Youtube deleted 90 percent of hate speech videos reported by users - but Twitter only deleted one percent. Facebook did a little better at 39 percent.

"We do not accept the fact that companies in Germany do not adhere to the law," Justice Minister Heiko Maas (SPD) told public broadcaster ARD in April, explaining why the new legislation was necessary.

Skeptics criticize, however, that under the new rules social media managers are the ones who have to decide whether content complies with German law. They also worry that freedom of speech will suffer since, in their opinion, companies are likely to delete many posts just to be on the safe side and avoid fines.

Maas said the new law didn't curb freedom of speech but was rather a prerequisite for it. To counter the criticism, the legislation also stipulates the establishment of an independent regulatory institution to which Facebook and other sites can pass on content when they're not sure whether it should be deleted. Investigators there will then make the final decision.

Landmark legislation in Europe

In addition to the strict new rules about deletion, the law forces networks to reveal the identity of those behind the hateful posts and to offer users "an easily recognizable, directly reachable, and constantly available" complaint process for "prosecutable content," which includes libel, slander, defamation, incitement to commit a crime, hate speech against a particular social group, and threats.

Germany is the first country in Europe to introduce such clear legal guidelines against online hate speech.