Dinn was a friend of Dunphy's, who would regularly come by the house and hang out, chatting and watching TV.
Dunphy was shot and killed on Easter Sunday, 2015, in his Mitchell's Brook home by Royal Newfoundland Constabulary (RNC) officer Joe Smyth.
Smyth was at Dunphy's house assessing a potential threat based on tweets Dunphy directed at then-premier Paul Davis.
Smyth has said that Dunphy pointed a rifle at him while sitting in his chair in the living room, and that's why Smyth shot and killed him.
But Dinn said in all the times he was inside Dunphy's house, he never saw a gun.
Dinn said that he usually saw a long, heavy stick with duct tape wrapped around one end as a handle.
"That's all I need for protection," Dinn recalled Dunphy saying.
Dunphy's daughter, Meghan Dunphy, has theorized that Smyth may have tampered with evidence in the minutes after the shooting and pulled the .22 rifle from lying on the floor behind the sofa where it was kept.
The allegation was that Dunphy might have pointed the stick at Smyth, and it was mistaken for a gun.