The government is contemplating tactics against the UK riots that set dangerous precedents.

In parliament today, prime minister David Cameron said authorities and the industry were looking at "whether it would be right to stop people communicating via these websites and services when we know they are plotting violence, disorder and criminality". Well, at least he did post it as a question of right and wrong.

It would be wrong, sir. Who is to say what communication and content should be banned from whom on what platform? On my BlackBerry? My computer? My telephone? My street corner?

Cameron also said, according to a Guardian tweet, that he would look at asking online services to take down offending photos. Again, who decides that content is offending? If you give authority to government and telco and social companies to censor that, what else can and will they censor?

Beware, sir. If you take these steps, what separates you from the Saudi government demanding the ability to listen to and restrict its BBM networks? What separates you from Arab tyrannies cutting off social communication via Twitter or from China banning it?

This regulatory reflex further exposes the danger of British government thinking it can and should regulate media. Beware, my friends. When anyone's speech is not free, no one's speech is free. I refer the honourable gentleman to this . Censorship is not the path to civility. Only speech is.

There is also debate about tactics to restrict anonymity in public. Cameron wants police to have the authority "in certain circumstances" to require face masks to be removed: instead of a burqa ban, a hoodie ban. One MP in the current debate also suggested rioters be sprayed with indelible ink. In addition, Cameron said that CCTV pictures – and, one assumes, pictures on social networks and the afore-derided BBM – would be used to identity and arrest rioters. I understand the motive and goal to control crime. I don't necessarily oppose the moves, for I argue in Public Parts that what one does in public is public.

But again, be aware of the precedents these actions would set. Be aware how they could be used under other circumstances. In Public Parts, I compare the use of social media to identity Egyptian secret police from ID photos taken from their liberated headquarters with the use of social media to identity protestors in Iran. A tool used for good can be used for bad.

The bottom line of these debated tactics would be this: anonymity would be banned in public; it would require that one be public in public.

Right now, online, we are having many debates about anonymity and identity .

So now we need to look at how the public street in London compares with the public street on the internet, on Facebook, Twitter, BBM, blogs and newspapers. What government does on the streets it could do on the internet, and vice versa. Each is a form of a public.

I was just writing a post defending the need for anonymity and pseudonymity online for the use of protestors and whistleblowers and the oppressed and vulnerable. I was also writing to defend social services that try to require real identity as their prerogative to set the tone of their services (rather than discussing that in the context of Facebook or Google+, look at it in the context of, say, LinkedIn, where pseudonymity would rob it of its essential utility and value). I was going to suggest that services such as Google+ find a middle ground where real identity is encouraged – even with verification of true identity as an optional service – but pseudonymity is permitted, with more power given not to the service but to the user to filter people and media and comments on that basis (allow me as a user to, for example, read the comments of people who have the courage to stand behind their words with their names). There is much nuance to be grappled with in these issues and in these new circumstances.

But now come the UK riots and the debate over what to do about them, raising these same issues in a new context – the street – with a new player: the government. The proper debate, I argue in Public Parts, should be held not in the specifics of these matters but instead as principles.

Restricting speech cannot be done except in the context of free speech.

When debating public identity, one must decide what a public is.

These are not easy issues, any of them, in any of these contexts. So I would urge my British friends to be careful about enabling their government to impose restrictions on the public.