Three Indonesian soldiers appeared before a military tribunal in eastern Papua province to face charges over the alleged torture of Papuan civilians which was captured on video.
Yesterday's trial comes days ahead of a visit by US President Barack Obama to the South-East Asian country, on the heels of the Pentagon's announcement in July that it would resume ties with Indonesia's special forces.
The footage, posted online by human rights activists, showed soldiers applying a burning stick to the genitals of one of the unarmed men and threatening another with a knife.
The three defendants are from a infantry unit based in Nabire, Papua province.
Two other soldiers were called to appear as witnesses.
The incident occurred earlier this year in an area of Papua where Indonesian troops frequently clash with poorly armed separatist rebels from the indigenous Melanesian majority.
Rights groups including Amnesty International have demanded Indonesia punish the culprits and end an entrenched culture of impunity in the country's security forces.
President Susilo Bambang Yudhoyono said on Monday there was "no immunity" for members of the country's armed forces.