Updated

Former Liberian President Charles Taylor will hear Thursday whether appeals judges overturn his landmark conviction and 50-year sentence for aiding murderous rebels who unleashed a reign of terror in Sierra Leone's 11-year civil war.

Taylor became the first former head of state convicted by an international war crimes court since World War II when the Special Court for Sierra Leone found him guilty in 2012 of 11 counts of war crimes and crimes against humanity.

Judges said he provided crucial aid to rebels and helped plan attacks in return for "blood diamonds" mined by slave laborers in Sierra Leone and political influence in the volatile West African region.

His conviction was hailed as ushering in a new era of accountability for heads of state.