Two officials, speaking on condition of anonymity because they were not authorized to discuss the case, said no final conclusions have been made in the case. In recent weeks, however, investigators have grown more skeptical that 51-year-old Bill Sparkman died at the hands of someone angry at the federal government.
The officials said investigators continue to look closely at suicide as a possible cause of Sparkman's death for a number of reasons. There were no defensive wounds on Sparkman's body, and while his hands were bound with duct-tape, they were still somewhat mobile, suggesting he could have manipulated the rope, the officials said.
Sparkman's naked body was found Sept. 12 hanging from a tree yet in contact with the ground in a remote patch of the Daniel Boone National Forest near Manchester, Ky.
The strange case attracted national attention when it first came to light, prompting worries that it may be a sign of increased anger toward the federal government in the first year of Barack Obama's presidency.
Authorities say Sparkman died of asphyxiation where his body was found.
A spokesman for the FBI's Louisville field office declined to discuss any aspects of the case.
Capt. Lisa M. Rudzinski, commander of the state police post in London, declined to confirm that there was any new focus in the probe.
"The Kentucky State Police are continuing to investigate the death of William Sparkman and have yet to determine whether it is homicide, suicide or accidental," Rudzinski said. "The investigation is continuing."
If officials do determine Sparkman did not die because of his government work, that would likely mean a less prominent role for the FBI in the investigation, assisting the Kentucky authorities but not preparing to bring a case to federal court.
Sparkman's adopted son has been adamant the case is murder, and he is not alone in that opinion.
Jerry Weaver, one of the people who found the body during a gathering at a family cemetery, remained certain the death was a homicide. Weaver told The Associated Press this week that he recalled Sparkman's hands being close together.
Weaver also said the rope, which he described as thin like a clothes line, was wrapped around the high branches of two different trees as if for leverage. Sparkman's truck was found nearby, and Weaver said he saw Sparkman's clothes in the bed of the truck and a census worker placard sitting on the dashboard.
Weaver had previously told the AP that the body was naked, bound at the feet and hands, and gagged. He didn't see the word "fed" on the chest but did notice there was an identification tag taped to the side of his neck.
"He was put on display," Weaver said.
A friend of the dead man said he seemed as chipper as ever in the days before his death.
Gilbert Acciardo, a retired Kentucky state trooper who directs an after-school program at the elementary school where Sparkman was a frequent substitute teacher, said he spoke with Sparkman two or three days before he died and saw no signs that he was upset about anything.
"He was the same Bill Sparkman I always had contact with," Acciardo said. "I didn't notice any change in mood or behavior. He came bouncing in like he always did, with a smile on his face, cutting up with me."
Sparkman's body has been released for cremation, but Rudzinski, the state police commander, said authorities are still waiting to analyze some forensic evidence in the case.