He had a serious head injury and died at the scene.
Detective Constable Marcus Hunter said Mr O'Connor began drinking with two men at the backpackers about 8pm on Friday, March 5, before the trio decided to walk into town about 10pm.
They ended up at The Outback but Mr O'Connor was asked to leave as he had been seen by a bouncer falling asleep, and he was deemed too drunk.
The trio then moved to Good Home, on Victoria St, and after several rounds of drinks, Mr O'Connor was again asked to leave.
His two associates stayed at the bar.
Mr O'Connor's parents told Coroner Gordon Matenga they felt that the area where their son died was an accident waiting to happen as there was no barrier at the end of the street warning people that the road ended and there was a sheer cliff drop.
They accepted that their son was drunk and disorientated after being in Hamilton just 36 hours. Mrs O'Connor urged coroner Matenga to get the Hamilton City Council to put up signage warning people that the road came to an abrupt end.
Mr O'Connor had walked around the house of Anglesea St resident Greg Penniket, down a few stairs, up and over a raised bed garden before appearing to lose his footing.
When approached at home, Mr Penniket said Mr O'Connor must have grabbed on to his portable compost bin when negotiating the raised garden bed and possibly stumbled, as he fell among the foliage, through trees and down the approximately 6m drop below.
Mr Penniket said he often had people driving or walking onto his property as the road signage made it appear as though the road continued.
He was home at the time of Mr O'Connor's death but didn't hear a thing.
"He came right through my property and there was no doubt about it, the [police] dog sniffed around and picked up the trail. Whereas they had presumed he'd come straight down the driveway, like a lot of the cars do. The road doesn't have a turning bay so people think that it continues into our driveway."
Coroner Matenga said he did expect to deliver a decision but after hearing submissions from Mr O'Connor's parents he decided to reserve his decision to give himself time to investigate recommendations about signage.
However, he accepted Mrs O'Connor's submission that her son was intoxicated and made an "error of judgment" in heading the wrong direction before ending up on Mr Penniket's property and falling to his death.
"How or why he decided to take that path is a little flummoxing. He clearly was disorientated and just went south instead of north along Anglesea St ... why he did that there's no way we can tell and we just won't know."
Mr and Mrs O'Connor declined to comment outside court.