It may look just like an ordinary suite of city centre offices in Glasgow, but an extraordinary decision has been made in Portland House.
By Reevel Alderson
BBC Scotland home and social affairs correspondent
The bombing of Pan-Am flight 103 claimed 270 lives
Since September 2003, the Scottish Criminal Cases Review Commission has been investigating the conviction of Libyan secret service agent Abdelbaset Ali Mohmed al-Megrahi for carrying out the Lockerbie bombing.
On Thursday the commission, which is charged with investigating possible miscarriages of justice, published its report.
The document runs to more than 800 pages, with several volumes of appendices.
The effects of the decision will be profound.
The commission, which had to take on extra staff and an additional floor of Portland House to carry out its mammoth task, has referred the conviction back to the High Court for a second appeal.
That appeal will eventually be heard by a panel of five judges.
Megrahi has already had one appeal following his conviction in January 2001.
It was heard at Kamp van Zeist, the former Dutch air base where he and his co-accused, Al-amin Khalifa Fhima, were tried.
Abdelbaset Ali Mohmed al-Megrahi is serving a life sentence
Fhima was acquitted and flew home to Tripoli.
But in March 2002, a panel of five judges rejected Megrahi's appeal and he has been held in prison in Scotland ever since.
Even before then, an industry of conspiracy theory had grown up with claims of cover-up, fabrication and withholding of evidence. It shows no sign of abating.
Dr Jim Swire, the former GP whose daughter Flora was one of the 270 victims of the bombing of Pan-Am flight 103, remains convinced that a Palestinian terrorist, Abu Talb, was responsible. He is in a Swedish jail serving life for terrorism offences.
Others blame the Iranians for the bombing, which came shortly after the USS Vincennes blasted an Iran Air plane, filled with pilgrims travelling to Mecca, out of the sky.
The integrity of key witnesses has also been called into question; in particular that of the Maltese shopkeeper who said he sold Megrahi clothes, fragments of which were found wrapped around a fragment of the bomb timer.
Now, after more than three-and-a-half years, the commission said it believed the conviction was unsafe.
Sending the case back to the appeal court, it has put Scottish justice and the police investigation in the dock.