A man already serving a life sentence for the murder of a Calgary caseworker has been convicted in the killing of a fellow inmate at a maximum-security federal prison in Edmonton.

Brandon Newman was found guilty last week of manslaughter in the 2022 stabbing death of 33-year-old Bretton Fisher at the Edmonton Institution. Newman is currently incarcerated for the second-degree murder of Deborah Onwu, a caseworker who was stabbed 19 times at an assisted-living facility in Calgary in 2019.

Court heard that tensions escalated inside the prison after Fisher confronted Newman over the earlier killing, raising concerns about violence against a woman of African descent. Fisher allegedly warned Newman and another inmate, Cody Nicholls, that they would be attacked if they did not transfer to another unit.

The confrontation ended with Fisher being stabbed three times and repeatedly stomped on. Nicholls was also convicted of manslaughter in the prison killing.

Both men argued they acted in self-defence, but Court of King’s Bench Justice Nathan Whitling rejected that claim, finding the response went far beyond any threat posed. In his written decision, the judge said Newman and Nicholls were the aggressors throughout the altercation and their actions were disproportionate, even considering the seriousness of the threats.

The case highlights ongoing concerns around violence and safety inside federal correctional institutions in Alberta. Sentencing for both men will be scheduled at a later date.