He and other experts have said the victim may have been killed in a mob hit.
"Two in the back of the head," he said, describing mob-style murders of the era. "Bury them in the desert or Lake Mead if they didn’t want them found or leave them where they lay to make a statement."
WATCH: Was it a mob hit? Retired cold case sergeant explains theories after body found in barrel in Lake Mead
A group of boaters first discovered the barrel at Lake Mead's Hemenway Harbor May 1, 2022, according to the Clark County Coroner and Medical Examiner's office.
Authorities immediately suspected foul play when they found a gunshot wound to the man's body.
At the time, police told reporters they believed the victim had been killed sometime between the mid-1970s and mid-1980s, based on his clothing.
The construction of new housing developments has also unearthed human remains buried in areas that were previously outside town, Sutton said.
Las Vegas authorities said they would hold a news briefing with more details at 3 p.m. PT/6 p.m. ET.
Fox News' Louis Casiano contributed to this report.