The coroner made that ruling after examining the victim, 52-year-old Barry Groh of Park Avenue in Quakertown.
An autopsy performed Tuesday found that Groh had suffered a single gunshot wound. The bullet entered his upper left arm and then entered his chest, killing him, the coroner said.
Late Tuesday, Action News learned that Groh was shot with a high powered rifle from up to 300 yards away.
Police say it is illegal to use high powered rifles for hunting in Bucks County.
"That's obviously going to lead in a certain direction, as well," Richland Township Sergeant Richard Ficco said.
The circumstances surrounding this death remain under investigation. Sources tell Action News that investigators are following several leads in the case.
While Groh's death has been determined to be homicide, police say there is still a possibility that this was an accident.
"Coroner actually determined it to be a homicide, whether thats criminal, negligent or a hunting accident--because a homicide is the taking of a life by another," said Sgt. Ficco.
He was not wearing an orange vest at this time he was gunned down.
Groh's body was spotted Monday morning in a heavily wooded area along the 1100 block of California Road in Richland Township near Quakertown, Pa. He was partially submerged in Tohickon Creek. His legs and boots were visible.
According to investigators, Groh killed a 175 pound nine-point deer then dragged it almost 300 yards to a spot near Tohickon creek.
He called his wife of 25 years, Theresa, to get their son to help carry the buck. However, by the time his 19-year-old son Justin arrived, Groh had been shot.
"We're still just trying to figure out exactly how this could have happened and maybe where the positions were when it happened," said Sgt. Ficco.
Action News has also learned that investigators have taken the weapons of hunters that were known to be in the area to attempt to rule them out through testing.
By coincidence, former Montgomery County District Attorney Mike Marino was part of a hunting party that stumbled onto the body late yesterday morning.
At first, authorities thought Groh had a heart attack trying to bring the deer out of the woods. It was only later that they discovered the gunshot wound.
The victim's shotgun was found about 15 feet away, leaning against a tree.
On Tuesday, investigators from the Bucks County District Attorney's office were conducting 3D laser mapping in a half-mile square area near the creeks and adjacent farmland, hoping to develop information that would help their investigation.
Meanwhile, family members remembered Groh, an unemployed maintenance mechanic who was laid off from Ford in January, as a good man who loved the outdoors.
"He was a very good father, did everything with his boys. He was an avid hunter and fisherman and everything," said brother-in-law David Schueck.