Additional District Session Judge, Kalyani, Sandip Chowdhury, sentenced the woman, Keprion Bibi, a resident of Haringhata, to life imprisonment and also imposed a fine.
Two other accused, Ikrajul Mondal, the victim's husband and sister-in-law Beleara Bibi, were released due to lack of evidences against them.
According to the prosecution, Keprion Bibi had poured kerosene on her daughter-in-law, 23-year-old Ruksana Bibi, and set her on fire December 15, 2010.
Neighbours took Ruksana Bibi to the Kalyani JNM Hospital with 95 per cent burns as her mother-in-law and the two others fled.
Keprion Bibi was arrested and her son and daughter surrendered in court and got bail. Keprion Bibi was not given bail.
