Joint Base Lewis-McChord, Washington (CNN) -- The American soldier accused of killing 16 Afghan villagers in a shooting rampage is sitting in a military courtroom for the next week or more, hearing the evidence against him. 

The Article 32 hearing began Monday at Joint Base Lewis-McChord in Washington state to determine if a trial is warranted for U.S. Army Staff Sgt. Robert Bales, who could get the death penalty if convicted. 

The deadly shooting spree near a small U.S. base in Afghanistan's Kandahar province last March strained already tense U.S.-Afghan relations and intensified a debate about whether to pull out American troops ahead of their planned 2014 withdrawal. 

"He committed a mass killing crime, and we would like the court in the United States to implement justice and punish him according to the crime," Ahmad Zia Syamak, a spokesman for Afghan President Hamid Karzai, told CNN on Monday. 

Bales acted with "chilling premeditation" and was "lucid, coherent and responsive" when he left the remote outpost and went from house to house, gunning down villagers, Lt. Col. Joseph Morse, the Army's prosecutor, told the court. Women and children were among the 16 dead and six wounded, authorities said. 

"Nothing really justifies killing women and children in a noncombat situation," Bales' attorney, John Henry Browne, told CNN earlier. "But there may be explanations if that's true." 

Read more: Stunned friends recall good deeds of Afghanistan killings suspect 

The first soldier to testify Monday was Cpl. David Godwin, who said he watched a movie and drank Jack Daniels whiskey with Bales and another soldier, Sgt. Jason McLaughlin, just hours before the alleged attack. 
Are Bales' friends stunned by his actions?
Stunned friends recall good deeds of Afghanistan killings suspect 