The lawmaker, who has served just five months in her post, has for some time been under the spotlight after witnesses in the Kigali suburb mentioned her as being a prominent member of the notorious Interahamwe militia which spearheaded the 1994 genocide against mainly ethnic Tutsis, according New Times of Rwanda.
She was accused by former militia members for distributing uniforms and other equipment to bands of Interahamwe killers.
The court also found her guilty of setting up and supervising a roadblock at a place popularly known as "Escalier", near her house.
Thousands of roadblocks were set up all over the country during the Genocide to sort out people on ethnic basis. All those found to be Tutsis were killed.
The court was told that Nirere, who was a Deputy Governor in the former Byumba Prefecture in charge of social affairs, fled the advancing RPF troops in 1993 and moved to Kanombe, Kigali.
Witnesses said that because of her position as Deputy Governor, she wielded a lot of influence among the militia members.
It is not known whether, the legislator will appeal or not.
© Hirondelle News Agency