The American soldier, Staff Sergeant Robert Bales, charged with killing 16 Afghan civilians last year will recount the massacre as he makes his plea of guilty to avoid the death penalty in court on Wednesday.

"Under the terms of his agreement with Army prosecutors, Bales will plead guilty Wednesday at Joint Based Lewis-McChord south of Seattle, and a sentencing-phase trial will be held this summer to determine whether he receives life in prison with the possibility of parole, or without it,"CBS News  reported.

Bales, 39, was on his fourth combat deployment when he walked off of an outpost in the Panjwai district of Kandahar Province in March 2011 entering the perimeter of two surrounding villages stabbing and shooting people, resulting in the death of 16 - most of whom were children.

The event is often referred to in the media as the Kandahar Massacre.

His lawyers have blamed alcohol and other medications for the incident, and have hinted at 'post-traumatic stress disorder (PTSD) as a possible reason for his murder spree, citing earlier attacks on his base wherein a fellow soldier, presumed to be close to Bales, was severely wounded.

The Honorable Judge Col. Jeffery Nance will listen to Bales' plea and account of the events and is free to question him as closely as he so chooses; lawyers are expecting a lengthy Q&A session with the soldier.

One of his lawyers, John Henry Browne, said Wednesday will focus on the soldier's recollection of the events, getting a feel for Bales' decision to plea guilty.

"Tomorrow is going to be about what happened, then in August is going to be a jury trial about why it happened," Browne said. "Obviously avoiding the death penalty is out No. 1 goal.  We've accomplished that, assuming the judge accepts the plea, and he believe he will."

Bales is from Norwood, Ohio, graduated from Ohio State University, is married to Karilyn Bales, and has two young children.