The accused is jointly charged with Ulugia Lomalasi Laufili, another man from the village of Vaiusu, where the 20 year-old deceased also lived.
A former Attorney General currently working in a private law firm, Taulapapa Brenda Heather Latū, is prosecuting the police case.
It comes after the Attorney-General's Office declared a conflict of interest because the suspended sergeant had worked with state lawyers in the prosecution division.