As an avalanche of testimony overwhelms exiled dictator Hissene Habre, his lawyers have repeatedly employed one line of defence -- that there is no smoking gun linking him to the atrocities of 1980s Chad.
The 73-year-old is making history in the dock of a special tribunal in Senegal over his regime's brutality -- the first time a despot from one African country has been called to account by another.
Habre, who fled to Senegal after being deposed in 1990, is being prosecuted in his adoptive country's capital Dakar for war crimes, crimes against humanity and torture during eight years of repression.
Rights groups say 40,000 people were killed during a regime marked by fierce repression of opponents and the targeting of rival ethnic groups -- although an investigating commission says the real toll is likely to be far higher.
The dramatic climax to the opening act has been the evidence of Bandjim Bandoum, a remorseful top official in the regime's feared political police, the Documentation and Security Directorate (DDS).
"Records of the questioning of detainees came back from the presidency with annotations: E for 'execute'; L for 'set free' or V for 'seen'," Bandoum, a top officer in the DDS under Habre's regime, told the court on Wednesday.
"Once a statement was prepared by the DDS on a prisoner, only the president could request a release," he said, adding that Habre was "aware of everything that was happening" in the department's detention centres.
- Reasonable doubt -
Bandoum, who fled Chad to live in France, said DDS agents who challenged their orders risked their lives and the safety of their families.
"Even Habre's closest collaborators were afraid of him," he told the Extraordinary African Chambers.
Mbaye Sene, defending, attempted to cast doubt on the idea of Habre as an all-knowing, all-powerful head of the feared department, however.
"If you've never been to the presidency, you've never talked to him, tell me how Hissene Habre gave you orders," he demanded, cross-examining the witness, who replied that his instructions came from an immediate superior.
Sene conceded last week that DDS agents were responsible for "the acts of the organisation and some abuses" -- but insisted they had never consulted Habre over their mistreatment of prisoners.
Cross-examining prosecution witness Mahamat Hassan Abakar, head of a commission into atrocities committed under Habre, the lawyer demanded: "You say that the DDS was the president's 'thing' -- then prove it."
The tactic of introducing reasonable doubt into the narrative casting Habre as torturer-in-chief may appear to his legal team the only possible way of getting an acquittal, but it is a line which could prove hard to hold.
Daniel Fransen, a Belgian judge who led an investigation commission in Chad in 2002, told the court he had interviewed Galy Ngothe, one of Habre's closest aides, who said the dictator "listened live to interrogations via walkie-talkie".
"He sometimes asked for the name of prisoners and gave instructions on how to proceed," Ngothe said, according to Fransen.
- Electric cable -
Fransen, who indicted Habre in a separate Belgian procedure, also gave evidence on the testimony supplied by torture victim Khadija Hassan.
"They brought me in at 3:00 am. Hissene Habre smashed a flashlight into my eyes and told me that if I did not tell the truth, it would be the end of my life," Hassan was reported to have said.
"Then he tied me to a chair and strangled me with an electric cable," Hassan was quoted as saying.
Always silent, calm and still in his immaculate tunic and turban, Habre has listened to testimony after testimony since the trial resumed at the start of September following a lengthy adjournment.
He also has appeared unmoved as handwritten correspondence from the presidency to a minister dated from 1984 was read out to the tribunal.
"Monitor for prisoners of war in hospital. From now on no prisoner of war may leave the detention centre unless he is dead," it said.
The document was rendered in efficient, deft writing -- but expert witness Tobin Tanaka, a graphologist, could only conclude that it was "plausible" that Habre had written the instruction.
Habre refuses to recognise the legitimacy of the court and has decided not to cooperate with the ongoing hearings, forcing the panel of judges to appoint his defence.
If Habre is convicted, he can expect a sentence ranging from 30 years to life with hard labour, to be served in Senegal or another African Union country.