WASHINGTON (AP) — Investigators trying to solve the mystery of a census taker found hanging from a tree with the word "fed" scrawled on his chest are examining whether he manipulated the scene in order to conceal a suicide and make a life insurance claim possible for his son, law enforcement officials told The Associated Press.

The dead man's son, Josh Sparkman, said in an interview with the AP that he found paperwork for the private life insurance policy among the personal files of his father, Bill Sparkman, but wasn't sure of the amount or when it was taken out. He said authorities have told him nothing about the case and haven't produced a death certificate, which is usually needed to make an insurance claim.

Two law enforcement officials, who spoke on condition of anonymity because they were not authorized to discuss the case, said investigators were trying to determine whether Bill Sparkman committed suicide but altered the scene to make it look like a homicide, allowing his son to collect.

Life insurance policies typically do not cover suicides within a certain time period after the policy begins.

Sparkman said he was convinced his father was killed, in part because there were several items missing and apparently stolen from his car. Police have declined to comment about any of the items removed from the car except for a census computer, which was not found although its case was.

"If it's deemed suicide, there's no point in even looking at insurance," the son said. "There's no such thing as suicide insurance. The money is not the concern. I just want to know what happened to my dad."

Bill Sparkman's naked body was found Sept. 12 near a cemetery in a heavily wooded area of southeastern Kentucky. One of the witnesses who found the body said the 51-year-old was bound with duct tape, gagged and had an identification badge taped to his neck. Authorities have confirmed "fed" was written on his chest, likely in pen.

Sparkman, 20, who is unemployed, said he's convinced his father could not have committed suicide, even though law enforcement officials previously told the AP on condition of anonymity that they were looking closely at that possibility and increasingly doubted he was killed because of his government job, as was first feared.

There were no defensive wounds on Bill Sparkman's body, and while his hands were bound with duct tape, they still were somewhat mobile, suggesting he could have manipulated the rope, the officials said. He was found hanging from the tree yet was in contact with the ground. Homicide, suicide and an accident were all being considered as a manner of death, authorities said.

Kentucky State Police Capt. Lisa Rudzinski declined to comment Thursday on whether a life insurance policy connection was being probed. She said investigators still have not determined the manner of death and were still awaiting forensic tests.

Sparkman said he also received a letter from the Census Bureau about how to collect his father's final payroll check and information about death compensation the government might owe him.

"It's not much, nothing substantial," he said. "It's not like it's enough to pay off the house or anything."

Because he was a census employee, Bill Sparkman's family would be eligible for up to $10,000 in death gratuity payments if he was killed on the job, according to the Office of Personnel Management. He was not eligible for a separate life insurance policy through the government because his census work was intermittent, Census Bureau spokesman Stephen Buckner said.

Sparkman said his father last updated his will in 1993, listing Josh as the heir to the estate, including the London, Ky., home valued at $80,000, according to Laurel County property records. Friends chipped in to help gather money for him to make one monthly mortgage check, but the son said he remains behind on other payments.

"My dad never really cared about material things," he said. "It's not what mattered to him. His friends, his family — that's the kind of stuff you care about. He would do without to see someone in his family do better."

Sparkman said he noticed no changes in his father in the weeks before his death that would suggest he was upset about anything. In their final phone conversation, his father mentioned he was still trying to land a full-time teaching job but remained upbeat, he said.

McMurray reported from Lexington, Ky. Hope Yen in Washington contributed to this report.