The dispute over who killed 14-year-old Samuel Weaver intensified today when Larry Cooper, a federal marshal involved in the gunfight at Ruby Ridge, testified that he thought it was Randy Weaver himself who fired the fatal shot that killed his son. TIME's Elaine Shannon believes Cooper's testimony raises important questions about Randy Weaver's possible complicity in the shootout, which also left another U.S. marshal dead. Says Shannon: "Weaver wants us to believe that he fired his gun in the air to call his son back home after the marshals began firing." Samuel Weaver was killed by a bullet fired from a 9mm weapon. Both Randy Weaver and Cooper have admitted firing 9mm guns at approximately the time that Samuel Weaver was fatally wounded.