Scottish police had information that might have changed the outcome of the Lockerbie bombing trial, a BBC TV programme has learned.
The information could have affected the credibility of key evidence, but was not passed to the defence team.
Libyan national Abdelbaset ali Mohmed al-Megrahi is serving life for killing 270 people in the 1988 bombing.
But there have always been doubts expressed about who was behind the bombing and what was their motivation.
He admitted to the programme's producer Guy Smith that the Libyan government had merely accepted responsibility for the Lockerbie bombing in order to get international sanctions lifted.
"Yes, we wrote a letter to the Security Council saying we are responsible for the acts of our employees... but it doesn't mean that we did it in fact.
"I admit that we played with words - we had to.
"What can you do? Without writing that letter we would not be able to get rid of sanctions."