For decades, Blaise Compaoré, the president of Burkina Faso, preferred to avoid the subject of Thomas Sankara, his predecessor and one-time friend who was brutally killed in 1987 by soldiers who gunned him down outside his office.
On Wednesday, a military tribunal confirmed longstanding, widespread suspicions that Mr. Compaoré, now in living in exile, was in fact behind the killing. The tribunal convicted him in absentia and declared a sentence of life imprisonment.
The heavily protected courtroom in the capital, Ouagadougou, erupted in applause after the sentence was read out — the climax of a much anticipated attempt to deliver justice for one of Africa’s most infamous political assassinations.
“This is a relief,” said Paul Sankara, the slain president’s younger brother, speaking by phone about the verdict. “It’s been a long wait.”
Thomas Sankara, a firebrand Marxist revolutionary, became one of the youngest presidents in modern African history when he rose to power in 1983. Over four years in office, he quickly gained a reputation for principled rule and spirited defiance of the West that earned him adulation across Africa.
He and 12 other men were killed in October 1987 during a military coup that brought to power his once close friend, Mr. Compaoré. For the next 27 years Mr. Compaoré ruled Burkina Faso with a tight grip until a popular uprising pushed him out in 2014, forcing him to flee to Ivory Coast with the help of French soldiers.
Mr. Compaoré, however, is unlikely to spend any time in jail soon. He refused to return to Burkina Faso for the trial, and Ivory Coast declined to extradite him. He has always denied any role in the killing, although his justification has changed over the years.
Mr. Sankara’s widow, Mariam, who has lived mostly in France since her husband was killed, was in the front row of the courtroom in Ouagadougou.
“I am satisfied,” she told The Associated Press, adding that she wished “the main suspects” in the case were also present.
Pierre-Olivier Sur, a French lawyer for Mr. Compaoré, said in an interview that his client refused to appear before a “puppet trial” that had taken place in “chaotic and dramatic” conditions.
The trial started at a repurposed convention center near the presidential palace in October, 34 years after the death of Mr. Sankara at the age of 37. Despite the challenges of mounting a trial decades later, a panel of civilian and military judges heard evidence from over 100 witnesses against Mr. Compaoré and 13 others accused in the killing.
The proceedings were briefly delayed in late January after the military seized power, the latest in a series of coups to afflict the landlocked West African nation since it gained independence from France in 1960.
On Wednesday tribunal also delivered sentences of life imprisonment against Hyacinthe Kafando, Mr. Compaoré’s former head of security, and Gen. Gilbert Diendéré, a senior army commander at the time of the assassination.
Eight other people, mostly former soldiers, received sentences of between three and 20 years. Three others, who were accused of creating a false death certificate for Mr. Sankara, were acquitted.
Like Mr. Compaoré, Mr. Kafando was not present in the courthouse, having gone into hiding years ago. General Diendéré has been in prison since 2015 for his part in a failed coup attempt.
Understand the Coup in Burkina Faso
Seizure of power. On Jan. 24, the military in Burkina Faso ousted President Roch Marc Christian Kaboré, the country’s democratically elected leader. Here is what to know:
Mr. Sankara is still a revered figure in Burkina Faso, and since the ouster of Mr. Compaoré in 2014, his legacy has been openly celebrated. Visitors flock to a giant bronze statue of Mr. Sankara, yards from the spot where he was killed, and his image adorns cars, motorcycles and T-shirts across the capital.
The trial represented an effort to establish the truth about his death, as well as a rare if belated attempt to impose justice for a military coup in a region with a long history of military takeovers.
“This is an historic verdict,” said Serge Martin Bambara, a popular rapper and democracy activist known by his stage name Smockey. “It shows that nobody is untouchable.”
Still, the coup that interrupted the trial in January, ousting Burkina Faso’s democratically elected president, Roch Marc Christian Kaboré, and bringing to power yet another military leader, belied hopes that the Sankara trial would act as a deterrent to future military coups.
And the trial avoided longstanding questions about the potential role of outside powers in the death of Mr. Sankara, including France, the former colonial ruler of Burkina Faso, and neighboring Ivory Coast.
One witness described how French officials visited Burkina Faso’s intelligence service one day after the killing, and removed sensitive surveillance materials. But the trial mostly avoided the subject of any international role, which the Burkina Faso authorities have reserved for a separate investigation.
Now that the trial is over, the Sankara family hopes to hold a proper funeral for the assassinated leader, who was buried in a pauper’s grave dug by prisoners at night within hours of his killing in 1987.
“This is not a moment for satisfaction,” said Paul Sankara. “But at least now we can grieve.”
As for the absent Mr. Compaoré, once considered a son by Mr. Sankara’s parents, he said simply: “He has his own conscience.”
