The 40-year-old Scot is accused of hacking into 97 US military and space agency computers in 2001 and could face up to 60 years in prison if convicted following his extradition.
UK Home Secretary John Reid granted the US request to extradite him for trial, but McKinnon’s lawyers argued that he had been subjected to "improper threats" and the transfer would breach his human rights.
However, Lord Justice Maurice Kay and Justice Sir John Bernard Goldring said that they did not find any grounds for appeal and dismissed his legal action.
McKinnon’s case dates back to 2001 when he allegedly hacked into 97 federal government computers. American prosecutors have accused him of accessing hundreds of military machines.
The former computer systems administrator admitted breaking into the systems, but said he was looking for evidence of UFO activity and was only motivated by curiosity.
Authorities maintain that he committed the "biggest military computer hack of all time" and caused around US$700,000 worth of damage.
Extradition proceedings began in 2005.
Pentagon hacker could face 60 years in prison after extradition to US
By Fiona Raisbeck on Apr 4, 2007 10:29AM
Gary McKinnon, accused of hacking into Pentagon and NASA networks, has lost his fight against extradition to the United States in front of the British High Court.
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