Long before the age of social media, legal systems have imposed restrictions on free speech. Some are for widely accepted reasons, such as to avoid libel or inciting violence. Many governments also impose restrictions, though typically in the name of national security or public safety, to protect themselves by stifling the capacity for dissent.

Historically, all such laws have focused more on public broadcasts than private conversations, not least because of the practical difficulty of monitoring interactions among friends. Social media, however, has blurred the old distinction between private conversation and public broadcast.

In recent years, legislators have been explicitly addressing this grey area created by social media. Almost always, the upshot has been to place tighter restrictions on freedom of speech.

In the United Kingdom, for example, when bad weather forced the cancellation of a flight to visit his girlfriend, Paul Chambers tweeted his frustration – “I’m blowing the airport sky high!!” – in words he expected to be understood as obviously facetious. He was arrested and convicted of sending “by means of a public electronic communications network a message [of a] menacing character”.

Though the conviction was later overturned on appeal, UK authorities continue to take a hardline approach to social media. Earlier this year Christopher Hay, a football fan in Glasgow, was arrested and prosecuted (although not convicted) for “intending to cause fear or alarm” when he tweeted, to 23 followers, that he “wish[ed] that someone would kill” a rival team’s manager.

Such stories make the international headlines because they seem like an absurd use of police time: the remarks are intemperate, but if they were made offline they would be subject only to social censure, not legal force.

While social media users in the UK should have learned to think twice before pressing the “Tweet” button in anger, for dissidents in many regimes with more stringent restrictions on speech the trend towards criminalizing social media activity has deeper implications. In March this year, for example, two men were sentenced to prison in Saudi Arabia after they tweeted information about planned protests.

More countries are introducing laws explicitly stipulating what can be said on social media, often with worryingly wide wording. The United Arab Emirates passed a law in 2012 allowing for the imprisonment of anyone who uses information technology to “harm the reputation” of leading officials, or to “advocate change” in the country’s system of governance.

As a human rights activist in Bahrain – a small country, where monitoring media use is relatively easy – I have learned to be extremely cautious about what I post on social networks. Many friends have quit sites such as Facebook and use only private messaging apps. Some are concerned enough to have stopped using social media networks altogether.

Others have sought to preserve anonymity online, by posting under pseudonyms using a VPN or the encrypted Tor browser. However, it is harder for activists to establish visibility and credibility if you are not willing to identify yourself publicly.

As well as taking legal action against individuals for what they write on social media, governments can act against the platform itself to censor what users post. There are commendable examples of refusals to comply – the blogging platform WordPress.com, for example, was temporarily blocked in its entirety in Turkey in 2007 when it refused to take down a blog the courts objected to. But few platforms are as willing to take such a principled stand when it means losing revenues.

Laws can be changed only in the countries which impose them, and often protests are unsuccessful. In February, Turkish activists demonstrated against proposals to allow the authorities to demand web pages are taken down without a court order, but the law passed parliament nevertheless.

However, there is one thing social media users all over the world can do: withdraw custom from platforms which acquiesce in censorship, and support those which take a more principled stand. If we want to ensure that social media evolves to facilitate democratic debate, rather than facilitate government attempts to shut it down, this may be our most effective point of pressure.

Part of a series on the top ten trends in social media

Author: Esra’a El Shafei is the Founder and Executive Director of Mideast Youth, Bahrain, which creates platforms and web applications that promote freedom of expression and social justice.

Image: A customer uses a computer in an internet cafe at Changzhi, Shanxi province January 25, 2010. REUTERS/Stringer