A policeman is on duty outside a court in Christchurch of New Zealand, on Aug. 24, 2020. The High Court in Christchurch of New Zealand started Monday the sentencing hearing of the gunman in the Christchurch mosque shootings, who killed 51 people, mostly worshippers, on March 15, 2019. The 29-year-old Australian, Brenton Tarrant, appeared emotionless as his actions on the day of shooting in two Christchurch mosques were detailed in court for the first time. (Photo by Zhu Qiping/Xinhua)

A policeman is on duty outside a court in Christchurch of New Zealand, on Aug. 24, 2020. The High Court in Christchurch of New Zealand started Monday the sentencing hearing of the gunman in the Christchurch mosque shootings, who killed 51 people, mostly worshippers, on March 15, 2019. The 29-year-old Australian, Brenton Tarrant, appeared emotionless as his actions on the day of shooting in two Christchurch mosques were detailed in court for the first time. (Photo by Zhu Qiping/Xinhua)

Policemen are on duty outside a court in Christchurch of New Zealand, on Aug. 24, 2020. The High Court in Christchurch of New Zealand started Monday the sentencing hearing of the gunman in the Christchurch mosque shootings, who killed 51 people, mostly worshippers, on March 15, 2019. The 29-year-old Australian, Brenton Tarrant, appeared emotionless as his actions on the day of shooting in two Christchurch mosques were detailed in court for the first time. (Photo by Zhu Qiping/Xinhua)

Policemen are on duty outside a court in Christchurch of New Zealand, on Aug. 24, 2020. The High Court in Christchurch of New Zealand started Monday the sentencing hearing of the gunman in the Christchurch mosque shootings, who killed 51 people, mostly worshippers, on March 15, 2019. The 29-year-old Australian, Brenton Tarrant, appeared emotionless as his actions on the day of shooting in two Christchurch mosques were detailed in court for the first time. (Photo by Zhu Qiping/Xinhua)