Mr Ghailani was captured in 2004 in Pakistan The first Guantanamo detainee tried in a US civilian court has been found not guilty of all but one of 286 terror charges over the 1998 bombings of US embassies in Africa.
Tanzanian Ahmed Ghailani was found guilty of conspiracy to damage or destroy US property with explosives.
But he was cleared of many other counts including murder and murder conspiracy.
Ghailani faces a minimum of 20 years in prison. The verdict comes as the US weighs other civilian terror trials.
Witness barred
The Ghailani case concludes the first test of the Obama administration’s decision to try some Guantanamo inmates in civilian courts rather than in military tribunals – or have them detained indefinitely.
Prosecutors suffered an early setback when federal Judge Lewis Kaplan in New York barred a key government witness from testifying, saying he had been named by Ghailani while the latter was “under duress”.
The witness, Hussein Abebe, had been expected to testify that he had sold TNT used in the bombing of the US embassy Tanzania in August 1998 to Mr Ghailani.
Mr Ghailani was detained in Pakistan in 2004, taken to a secret CIA facility and then to Guantanamo Bay in 2006.
He was subject to what the government refers to as “enhanced interrogation” by the CIA. His lawyers say he was tortured.
Ghailani’s defense attorneys had argued he was duped by al-Qaeda operatives.
Among those the US has said it hopes to try in a civilian court is alleged 9/11 mastermind Khalid Sheikh Mohammed.
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