Tharcisse Renzaho was born in 1944 in the Gaseta sector of the Kigarama commune, which is situated in the Kibungo prefecture of Rwanda.
Tharcisse Renzaho received his education as a military engineer in various military academies in Germany, France and Belgium. He took up politics in 1990, and was appointed préfet of the prefecture of Kigali City. At that same time, he held the position of President of the Civil Defence Committee for Kigali City. His de facto and de jure authority was extensive and covered the mayors, the sector councillors, administrative personnel, gendarmes, cantonal police, the Interahamwe, the militias and armed civilians. In his position as Colonel in the Rwandan Armed Forces (FAR), Renzaho was a senior officer who wielded control over the armed forces placed under his command.
Towards 7 April 1994, and on a regular basis thereafter, Tharcisse Renzaho was said to have given out orders during meetings, orders which were also broadcast by air over Radio Rwanda, and which were directed at the military, gendarmes, militias, local citizens and demobilised soldiers, requiring them to set up and man roadblocks with the intent of intercepting, identifying and then killing Tutsis.
Towards 9 April 1994 in Kanombe (prefecture of Kigali-City), the Interahamwe militias broke into houses belonging to the Tutsis, killing them in the presence of Tharcisse Renzaho, who, despite his position as high level civil servant, reportedly did not put up any opposition.
Towards 30 April 1994, Renzaho was said to have dismissed sector councillors Jean-Baptiste Rudasingwa and Celestin Sezibera, since both of them were opposed to the murder of Tutsis. Based on reports, they were subsequently replaced by councillors in favour of the massacres.
According to the prosecutor, towards 18 April 1994, Renzaho, accompanied by Wenceslas Munyeshyaka, ordered the detention of around 40 people, for the most part, Tutsis, at the CELA (Centre for the Study of African Languages). On 22 April 1994, in the company of Odette Nyirabagenzi and Angeline Mukandutiye, he was reported to have issued an order to bring out and kill around sixty Tutsi men detained in the CELA. On 14 June 1994, whilst in the company of these two women, he was said to have ordered the killing of around sixty Tutsi boys at the church of Saint Paul and on 17 June 1994 to have ordered the attack on the refugees in the church of the Holy Family, where many Tutsis were massacred.
According to the indictment, Renzaho, on several occasions, ordered and participated personally in the distribution of firearms.
In May 1994, he furnished several Kalashnikov rifles to Bishop Samuel Musabyimana rifles which were delivered by Major Nyirahakizimana. These rifles were subsequently distributed to the militias who used them to massacre Tutsis.
Between April and June 1994, Renzaho was suspected of sending out Interahamwe militias with precise instructions to kill certain selected persons. Amongst those selected was the journalist André Kameya, a strong critic of the interim government.
From April to July 1994, according to the indictment, Tharcisse Renzaho facilitated the delivery of arms, vouchers, official permits, safe-conducts and foodstuffs in order to provide support to the Interahamwe militias.
On the fall of the interim government in July 1994, after the military victory of the Rwandan Patriotic Front, Tharcisse Renzaho fled into exile.
In 1997, he escaped a police trap laid conjointly by the Kenyan police and the ICTR investigators. In December 2005 he gave the slip to an operation organised by the ICTR which was aimed at arresting certain ex officers of the FAR who had gone into hiding in Zambia.
Tharcisse Renzaho was finally arrested on 26 September 2002 in the Democratic Republic of Congo(DRC). On 29 September 2002, he was turned over to the International Criminal Tribunal for Rwanda.