ISTANBUL In Court Number 6 in Diyarbakir, the main city in the mainly Kurdish southeast, Turkey is examining its recent history.
Along with six others, Colonel Cemal Temizoz stands accused of at least 20 killings during his time as a paramilitary commander in Cizre, a town in Sirnak province on the Syrian border, between 1993 and 1995.
Never before has such a senior uniformed figure faced trial for crimes committed during Turkey's bloody counter-insurgency campaign against ethnic Kurdish separatists.
Lurid testimony has been given of severed ears threaded as prayer beads and corpses disposed of in wells of acid. The web of evidence includes jailhouse testimony from a brother of Cizre's former mayor and the discovery of human remains.
For over 25 years the Kurdistan Workers' Party or PKK, a group designated a terrorist organisation by Turkey, the European Union and the United States, has fought an armed struggle in pursuit of a separate Kurdish state.
The conflict has cost tens of thousands of lives and led to a stream of internal migration away from the affected areas.
While human rights campaigners and the families of the dead have welcomed the Temizoz trial, the case also highlights the problems Turkey faces in reaching any settlement with its past.
Prime Minister Tayyip Erdogan, the leader of the Islamic-leaning Justice and Development Party or AK, has tried to expand the rights of minority Kurds.
Nationalist rivals fiercely oppose Erdogan's initiatives, but so do many AK supporters. An election is due next year, and the AK has to protect its vote bank to win a third term.
The influence of conservative, secular nationalists opposed to AK has waned, but they remain a force to be reckoned with in a country that has become increasingly polarised since the AK shot to power in 2002.
The old elite's strongholds remain the military and the judiciary and the courts have become a battleground.
"Turkey is dealing with issues of transitional justice while the transition is not over yet," said Gerald Knaus, a fellow at the Carr Centre for Human Rights Policy at Harvard University.
While South Africa and some Latin American nations have tried to address past human rights abuses after a complete change of regime, Turkey is trying to address its past without such a dividing line between old and new governments.
At the same time it is taking steps to strengthen its democracy, having seen its military topple four governments in the last 50 years.
"What is happening in Turkey at the moment does not happen usually in countries where there is no big rupture," said Kerem Oktem, an academic at St. Anthony's College in Oxford.
RESPECT FOR MILITARY
For decades the idea endured that the military stood above civilian authorities as guardian of the secular values of the modern republic founded in 1923 by Mustafa Kemal Ataturk.
Today that notion is changing. There is still enormous respect for the military and Ataturk's portrait adorns classroom and office walls across the country.
But Turks, confident that democracy will bring prosperity and opportunity, do not want any more coups, and many believe the armed forces must be subject to the same laws as the rest of the country.
The ruling AK party has drafted constitutional amendments that would, among other changes, make military officers liable for prosecution in civilian, rather than military, courts.
Much of the current focus on the past stems from the Ergenekon investigation, a probe into the supposed 'deep state' -- a secret group of hardline nationalists in the security forces and bureaucracy determined to uphold secular values.
Named after a mythical Central Asian valley where Turks are said to have been saved from annihilation by a wolf that led them past their enemies, the Ergenekon network was said to have been planning the overthrow of Erdogan's government.
The investigation began in 2007 and as it gained ground, Turks watched in amazement as a procession of senior military figures, both serving and retired, appeared before prosecutors.
There was public support from the outset, but some have voiced the suspicion that the AK may have been using the probe to attack its political opponents.
Some think the number of cases, which has expanded to include events that happened after the Ergenekon investigation began, is too big for the judicial system to handle.
Others doubt whether the Ergenekon network even exists.
But Ergenekon has certainly broken taboos -- in particular by bringing previously untouchable military figures before prosecutors -- and opened the way for other investigations.
It has also proved the value of liberalizing statutes passed as part of Turkey's bid for EU membership.
"The Ergenekon investigation created an atmosphere which allowed us to deal with the other cases," said Orhan Kemal Cengiz, a columnist for the Turkish newspaper Today's Zaman.
Emma Sinclair-Webb, a researcher with Human Rights Watch in Turkey, said Ergenekon helped make it possible to bring the Temizoz case to court.
"It provided the inspiration and an impulse in the region for people to come forward, and for the press to cover the issue," she said.
In Diyarbakir, Temizoz is under arrest but is still commander of the provincial gendarmerie battalion, and Tahir Elci, a lawyer for the victims' families, fears the trial could end up in a military court.
"Until now I am happy with the case, but I also worry about future developments," he said. "The other side is trying to transfer the case to the military courts."
(Edited by Simon Cameron-Moore and Tim Pearce)