Will the last one to leave please switch off the server

It had to happen. During the months of controversy surrounding the government's Snooping Bill we've been waiting to see how far opponents of the legislation were prepared to go.

Now the union's union, the TUC, has said it is prepared to move its email services abroad rather than risk giving the police access to its members' messages.

And Poptel, one of the country's largest ISPs and the TUC's service provider, will make this easy, because it is moving its servers out of the UK.

Why are the unions so upset? The Snooping Bill - officially the Regulation of Investigatory Powers Bill - potentially gives police access to communications data of anyone suspected of committing a serious crime.

Tucked away at the back of the Bill, one of the Home Office's definitions of serious crime reads: "conduct by a large number of persons in pursuit of a common purpose".

Combine this with the fact that campaigners have found a loophole in the Bill which would allow law enforcement agencies to trawl any email sent internally within the UK for specific keywords (paedophile, terrorism or, who knows, industrial action) and you can see why the unions are getting so edgy.

Whatever the rights and wrongs of the argument it illustrates a fatal flaw in the government's plan.

You can only access people's emails with the right equipment - a so-called 'black box' - attached to an ISP's servers. Move servers outside the UK and where does that leave Home Secretary Jack Straw and friends?

No one is arguing against the right of law enforcement agencies to track criminals - whether that's by phone, post or email. But with only three days left before the Bill leaves the House of Lords, perhaps its time to get some perspective.