Marital homicide practiced by women occurs mainly in contexts of victimisation. This text presents a qualitative study carried out through the thematic content analysis of semi-structured interviews and the documentary analysis of the individual prison cases of six Portuguese female inmates convicted of the murder of their partners or former partners, looking for a possible relation between the practice of crime and exposure to a prior history of intimate gender violence, as well as problematising their defence before the criminal justice system. It was concluded that all were victims of gender-based violence on the part of their partners and that there are gaps in the criminal justice system regarding the conviction of these women.