He was a moderate figure who had originally joined the Rwandan Patriotic Front (RPF) in 1992 and served in the post-genocide government of national unity.
However, he eventually fell out with the leadership over human rights concerns, specifically criticizing the army’s treatment of civilians.
In 1995, he left the government and went into exile in Kenya, where he founded an opposition group called the Forces de Résistance pour la Démocratie (FRD).
His death followed an earlier unsuccessful attempt on his life in February 1996, where he and his nephew were wounded in Nairobi
Following that first attack, Sendashonga identified one of the assailants as an employee of the Rwandan embassy, an event that led to significant diplomatic tension and the expulsion of Rwandan diplomats from Kenya.
Despite the constant threat to his safety, Sendashonga remained an active political voice and was prepared to testify as an expert witness before the International Criminal Tribunal for Rwanda (ICTR) and a French parliamentary commission.
The final assassination took place on May 16, 1998, as Sendashonga was being driven through Nairobi’s Parklands suburb in a car belonging to the United Nations Environment Programme (UNEP), where his wife worked.
Two gunmen using AK-47 rifles fired at the vehicle, killing Sendashonga instantly and fatally wounding his driver, Jean-Bosco Nkurubukeye.
The attack occurred near the junction of Limuru Road and Forest Road (now known as Prof. Wangari Maathai Road).
The subsequent investigation and trial in Kenya became a source of international controversy.
While three men were initially charged with the
murder, a Kenyan High Court judge eventually acquitted them in 2001, ruling that the prosecution had failed to link them to the scene.
The judge characterized the assassination as a "political" act and explicitly blamed the Rwandan government for the killing, noting that Sendashonga’s status as a witness who "knew a lot about the system" made his elimination imminent.