Twitter has announced plans to censor Tweets according to the laws in each user's country, which it says will allow it respect "different ideas about the contours of freedom of expression."
Users have reacted angrily to the restrictions, which they say amount to censorship.
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The move was announced in a post called 'Tweets Still Must Flow' on the official Twitter blog last night.
Twitter cited the example of France and Germany, where pro-Nazi statements are banned. Until now, the post said, Twitter was obliged to delete content that broke those laws on a global basis, so it would not be visible anywhere – even in countries where it was legal. However:
Starting today, we give ourselves the ability to reactively withhold content from users in a specific country — while keeping it available in the rest of the world. We have also built in a way to communicate transparently to users when content is withheld, and why.
Content will be blocked in response to "a valid and properly scoped request from an authorized entity," Twitter said on its support page.
When a Tweet is censored, a notice will appear reading: "This Tweet from @Username has been withheld in: Country." Twitter also said it would collaborate with Chilling Effects, an independent online rights monitor, to make all of its take-down notices public.
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Some commentators have expressed concern that the restrictions would allow undemocratic governments to stifle dissent. From PC World:
The obvious question here is what Twitter will do when freedom fighters, like those who participated in the Arab Spring last year, Tweet their dissent or use the service to organize protests. Will Twitter agree if a repressive government wants to silence their own people?
According to the Washington Post, many of the Tweets posted today under the protest hashtags "#TwitterBlackout" and "#TwitterCensored" were in Arabic.
Twitter did indicate that there were limits to the censorship it would agree to enforce, however. "As we continue to grow internationally," it wrote, "we will enter countries that have different ideas about the contours of freedom of expression. Some differ so much from our ideas that we will not be able to exist there."
Several Twitter users have vowed not to use the service on Saturday in protest at the new restrictions.
Others have worked out that there appears to be a simple way around them. Twitter will decide whether to restrict content according to which country you're registered in – but, as The Next Web explained, users can set their location to whichever country they choose by manually overriding Twitter's automatic IP address detection.
Indeed, the simplicity of the workaround prompted SlashGear to ask "whether the social network left such an obvious loophole open on purpose." If not, it said, the system is likely to be changed to make evading the restrictions more difficult.
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