|Staff Sergeant Bales is accused of killing 17 Afghan civilians in Kandahar province [US military newsletter]
A top US Army general has said that the case against US soldier Robert Bales, charged with 17 counts of premeditated murder over the pre-dawn massacre of Afghan villagers, is set to be a "long process".
General Lloyd Austin, the deputy chief of staff of the US army, was speaking from Joint Base Lewis-McChord shortly after Bales was officially charged on Friday.
Austin said that the charging of the staff sergeant was merely the first step in the process of trying the soldier.
In an interview on Friday, John Henry Browne, the attorney representing Bales, also spoke of a trial that could take years to iron out.
The Seattle-based attorney said of the impending case itself, "my first reaction to all of this is: prove it ... This is
going to be a very difficult case for the government to prove in my opinion. There is no CSI [crime scene investigation] stuff. There's no DNA. There's no fingerprints."
"All my cases start out with the government making as many charges as they can and then we spend months, years sometimes - in this case it will be years - whittling them down hopefully," Browne said.
Despite this projected years-long outlook for the case, former US Judge Advocate General (JAG) Colonel Lisa Windsor said there is increased pressure to begin prosecution in a high profile case with political implications for the strained US-Afghan relationship.
"You saw this in the Haditha case, people that were brought to trial so long after the fact in that case that it just made it very difficult after a while for the government to put a case together," said Windsor, referring to a 2005 case involving the killing of Iraqi civilians by a group of US soldiers.
Eight Marines were charged in that case, but plea deals and promises of immunity in exchange for testimony meant no prison sentences were ever issued.
The charges, made official on Friday, constitute a capital offence, which could see Bales facing the death penalty if found guilty.
Bales was officially informed of the 29 charges against him - including six counts of attempted murder and six counts of aggravated assault and other violations of military law for the wounding of six others - at the US military prison at Fort Leavenworth, Kansas, where he has been confined.
The decision to charge Bales, accused of walking off a US military base with his 9mm pistol and an M-4 rifle outfitted with a grenade launcher, with premeditated murder suggests prosecutors plan to argue he consciously conceived the killings.
An ISAF military legal official, speaking on condition of anonymity, noted that premeditated murder is not something that has to have been contemplated far in advance.
Legal experts have said the death penalty would be unlikely in the case.
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The US military has not executed a service member since 1961, when an Army ammunition handler was hanged for raping an 11-year-old girl in Austria. None of the six men currently on death row at Fort Leavenworth, where Bales is currently detained, were convicted for attacks against foreign civilians.
The killings - mostly of women and children - are believed to be the deadliest war crime by a NATO soldier during the decade-long war.
The maximum punishment for a premeditated murder conviction is death, dishonourable discharge from the armed forces, reduction to the lowest enlisted grade and total forfeiture of pay and allowances, Colonel Gary Kolb, an ISAF spokesperson said.
The mandatory minimum sentence is life imprisonment, with the chance of parole.
A senior US official said earlier that it had "pretty much been decided" the trial would be held in the United States.
The next procedural step will now be for an investigating officer to submit a written report on the sufficiency of charges and evidence against Bale. The contents of this report will aid the court in deciding how to address the charges.
Relatively few high-profile war crimes believed to involve Americans in the past century, have resulted in convictions.
Earlier on Friday, the news of Bales' then impending charges prompted dismay in Afghanistan, where a relative of many of those killed in the massacre called for Bales to be tried in the country.
Haji Samad, an elder whose family members were among those killed, said: "We want the prosecution of this American soldier in Afghanistan not in the US, because he committed the crime in Afghanistan.
"Why he is going to be prosecuted in the US? If this man is prosecuted in Afghanistan, we will be relieved. If he is prosecuted in the US, we will be angry and it will remain a pain in our hearts."
Upon hearing Bales had been charged, Wazir Khan, who lost 11 members of his family in the incident, asked for a swift trial and severe punishment for the 38-year-old US soldier for his alleged crime.
A Taliban spokesman said the group had no faith in any trial planned for the accused soldier, and called for revenge against US forces working in the country.
"This was a planned activity and we will certainly take revenge on all American forces in Afghanistan and don't trust such trials," Zabihullah Mujahid, the spokesman, told Reuters by telephone.
He reiterated claims held by many Afghans that there must have been more than one soldier involved in the massacre, a charge that US authorities have consistently denied.
"Now America tries to deceive the people and tries to blame the act on one soldier. This is a crime by the American
government. Using such cleverness and deception is a huge crime," Mujahid said.
Al Jazeera's James Bays, reporting from Kabul, said: "[The Taliban say] they don't feel that there will be a fair trial in the United States.
"I think they are looking at some of the comments that have come through in the press, talking about the background to this - why the soldier may have been pushed over the edge, why he may have carried out these killings."
Hamid Karzai, the Afghan president, speaking to a group of students in Kabul, referred to the victims of the March 11 shootings, including nine children.
"Kandahar children who are not with us any more, they are watching our youths up there from paradise and they are waiting to see if you move the country forward. So your hard work and struggle will rebuild our country and make their souls happy."