DNA from the body removed Thursday will be compared with DNA of missing people entered into a database. His DNA also will go into other databases.
The man in the Johnson County grave is known by police as "Mr. X." Nude and decomposing, Mr. X was found by a rancher on Dec. 11, 1972, in a field about 14 miles northwest of Cleburne.
An autopsy showed the man was shot three times in the chest and arm with a .25-caliber handgun.
"The best result we can hope for is to identify the individual and in doing that find out things that lead us to a suspect," James Ferguson, one of the investigators and a former assistant police chief at the University of Texas at Arlington, told the Fort Worth Star-Telegram.
"The killer might be getting a little old. Usually, suspects are about the same age as their victims. So this one would be in his 70s," he said.
The grave was unmarked, but retired Fort Worth police investigator Jim Varnon said good records kept by the operators of the cemetery led them to the site.
"They took us out and that depression in the ground is still there after 40 years," Varnon said
A backhoe was used to get down about 4 feet, and cemetery workers used shovels to reach what was left of the plywood box coffin. The remains of the body were inside a black plastic bag. Anthropologists using hand trowels did the last of the work, and then wrapped the bag in new plastic. The body was taken away in an ambulance.
Ferguson said the team has a couple of leads. One of them relates to an incident where a man shot at some employees at a Fort Worth bar. A detective at the time was told the employees would resolve the dispute themselves.
"The detective told them that he didn't want to see a body show up in Tarrant County," Ferguson said. "They said that wouldn't be a problem."
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