Acta is the latest copyright enforcement scheme to cause alarm among digital activists. Given its reach, this is understandable.

The anti-counterfeiting trade agreement is, despite its name, effectively an international treaty that forces signatories to criminalise "commercial-scale" copyright and trademark infringement. Some of it covers knock-off merchandise, but most applies to the digital world as well. Many of Acta's provisions already exist in countries such the US and the UK – for example, it makes sure courts can block or take down infringing websites – and the idea is ostensibly to bring the rest of the world in line.

However, some elements would go further than existing laws in most of the countries that sign up. Acta criminalises activities such as breaking the digital locks on rights-protected files, or even distributing tools to help people do so. Stripping the artist information from a music file becomes a crime, as does decrypting content that has been scrambled for copyright protection. Acta also codifies the flawed idea, in calculating damages from so-called piracy, that every unlawful download represents a lost sale.

One reason for the heightened attention being paid to Acta is the recent derailing of the Stop Online Piracy Act (Sopa) and the Protect IP Act (Pipa) in the US. These bills were, in many ways, more dangerous than Acta – Sopa wanted to alter the DNS, the core of the internet – but the spirit is the same. After winning a round against the US bills, citizens and activists are raring to take on a new challenge.

Acta was the brainchild of the US and Japan. Its formulation began in 2007, outside the frameworks of the World Trade Organisation and without the involvement of China, India and other countries that are major sources of pirated goods. Because it was technically a trade agreement, negotiations took place behind closed doors, with the only look-in afforded to citizens' groups or even elected representatives coming via a series of leaks.

Through conduits such as WikiLeaks, it became clear that the US in particular was pushing for signatories to create "three-strikes" laws that could be used to kick repeat file-sharers off the internet. The EU pushed back and this provision was removed, along with a requirement that ISPs and other online service providers snoop on their customers. The criminalisation of camcorder use in cinemas is also no longer mandated in Acta.

But what remains is troubling on several counts. Acta ostensibly targets big players, but, when it comes to its application on the internet, its definition of "commercial-scale" infringement is loose enough to also cause trouble for individuals. According to Acta, criminal and civil enforcement procedures "shall apply to infringement of copyright or related rights over digital networks, which may include the unlawful use of means of widespread distribution for infringing purposes".

Given that "widespread distribution" is the essence of the internet, this could be interpreted as a go-ahead for cracking down on small-scale infringers, or even people who post a copyrighted image or parody of it on their blogs. Sites and blogs that carry Google Ads could arguably also be seen as "commercial activities for direct or indirect economic or commercial advantage", another way in which Acta defines commercial scale.

Those defending Acta maintain that it would not bypass free speech and privacy safeguards in places such as the US and EU. The document itself regularly refers to a need for "freedom of expression, fair process, and privacy" in the way enforcement is carried out, but only in accordance with the laws of the signatory country. Some of those countries, such as Morocco, are not noted for providing a strong right to free expression. Even if Acta's apologists are to be taken at their word, the implications could be unpleasant for free-thinking citizens in many parts of the world.

It is no longer possible to change the contents of Acta, as it has been finalised. However, Acta is now, for the first time, in its democratic phase. Although 30 countries, including the US and UK, have signed Acta, no one has yet ratified it. The treaty may have been negotiated by governments and bureaucrats, but most of the signatories now have to get Acta through their legislatures. The process varies from country to country, but the document is finally in the hands of elected representatives.

Those who want to see Acta defeated need to go to their MPs, MEPs and congresspeople and ask them, facts in hand, to vote against its ratification. Even though elements of Acta may be needed to combat large-scale copyright and trademark infringement, it can be argued that the risks associated with the whole are too great. Elected representatives may be receptive – they themselves were shut out of the Acta negotiations and, after the Sopa protests, they are well aware that voters dislike heavy-handed copyright enforcement.

Agreements such as Acta are entirely driven by one side: the rights-holders. These players have a genuine grievance, in that the internet poses an overwhelming threat to their old business model. The copyright-versus-technology debate is worth having, and soon. But resolution has to come through genuine discussion between the content industry, lawmakers and the public.

The structures to allow this open debate will hopefully come, but not before the debate is reset. Right now, citizens have a rare and possibly brief opportunity to call for that to happen.

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