A white supremacist who killed 51 people at two New Zealand mosques will appear in court this week to try to withdraw his guilty plea. Australian Brenton Tarrant is serving a life sentence with no parole after admitting to murdering the 51 people and attempting to murder another 40 in the March 2019 attack on worshippers during Friday prayers in Christchurch. He initially denied the charges but changed his plea a year after the attack. The 35-year-old, who also admitted one count of terrorism, has now launched an appeal, filed out of time, arguing he was incapable of making rational decisions at the time because of 'torturous and inhumane' conditions in prison. He also wants to appeal against his sentence. The hearing at New Zealand's Court of Appeal in Wellington is scheduled to run all week, with Tarrant expected to give evidence via video link. The massacre at Al Noor mosque and Linwood Islamic Centre - parts of which were live-streamed - led to stricter gun laws in New Zealand. Victims and family members will be able to watch the hearing via a delayed broadcast with some family members, like Aya al-Umari, who lost her brother in the attack, expressing disappointment at being forced to relive traumatic memories. The court's decision on his appeal could potentially reopen the case for trial on all charges, which would be a significant moment for the victims’ families.