A U.S. Army soldier who prosecutors assert hatched the plan for the execution-style slayings of four bound, blindfolded Iraqis by the side of a Baghdad canal pleaded not guilty to murder at his court-martial Monday.

Master Sgt. John Hatley, 40, was charged with premeditated murder, conspiracy to commit premeditated murder and obstruction of justice in the shootings that took place in spring 2007 in the Iraqi capital.

At the hearing, Hatley, dressed in his green formal uniform, entered his plea to Army judge Col. Jeffrey Nance. A jury of eight soldiers — a mix of officers and non-commissioned officers — will hear the case, which is expected to last through the week.

If convicted, Hatley could be sentenced to life in prison without the possibility of parole.

Prosecutor Capt. Derrick Grace said it was Hatley who decided to kill the four men and that he, along with two other men — Sgt. 1st Class Joseph Mayo and Sgt. Michael Leahy — walked to the canal where the four Iraqis were and shot them dead.

"In a few days I ask you to come back here to find the accused guilty of all charges," Grace said, addressing the jury.

Hatley's civilian lawyer, David Court, said the case was based only only testimony, not actual evidence. The bodies of the Iraqis have never been found.