NASA hacker Gary McKinnon has been denied a UK trial.
McKinnon stands accused of breaking into US military computers, including those belonging to NASA, in 2001 in a bid to prove the US government had knowledge of UFOs.
In August 2008, the European Court of Human Rights agreed to allow McKinnon to be extradited to the US. However, McKinnon has been trying to change the decision with a number of moves that included informing the British Crown Prosecution Service (CPS), that he would enter a guilty plea if the case was heard in the UK.
Earlier today, the CPS revealed it was refusing to bring charges against McKinnon, which means he is one step closer to extradition.
McKinnon says his exploits did not cause any damage, but US authorities allege that he stole 950 passwords and deleted files at a naval base in New Jersey. They also maintain the intrusions disrupted computer networks used by the military that were critical to operations conducted after the September 11, 2001 terrorist attacks. The US estimates the damage caused by McKinnon at $700,000 (£470,000).
"What's fascinating about McKinnon's ongoing saga is that the IT community is showing a lot of sympathy for his plight, and today's news will come as a blow," said Graham Cluley, senior technology consultant at security firm Sophos.
"The real question is should we really be making such an example of a guy who was apparently just a UFO conspiracy theory nut? There's a danger that McKinnon is being used as a whipping-boy by a country embarrassed about the poor security of its computers in the months after 9/11."
Research conducted by PC Advisor in August last year revealed that over 50 percent of readers wanted McKinnon to stand trial in the UK. Mayor of London Boris Johnson was among those supporting McKinnon.
In a column in The Telegraph, Johnson called US efforts to prosecute self-acknowledged hacker McKinnon a "legal nightmare".