"I'll be making more inquiries, don't you worry about that," Reg McCormack said after an inquest hearing yesterday into the death of his son, Regan, on July 10 last year.
Mr McCormack and ex-wife Kay said after the hearing nothing done so far had given them "closure".
Police would investigate further if new evidence came to light, but in the meantime the case was effectively "cold", Mr McCormack said.
Mrs McCormack said they hoped the recommendations Coroner David Crerar signalled he would make around improving safety on the waterfront where Regan fell in would be taken up, so no other parent would have to go through what they had.
But there were still many unanswered questions about what happened to their son.
The court heard that Regan, a 20-year-old surveying student, was walking home from a 21st birthday party in central Dunedin the night he fell into the harbour.
He had been drinking and postmortem tests found 185mg of alcohol per 100ml of blood in his system. (For comparison, the legal blood-alcohol limit for drivers is 80mg.)Joshua Quinn, a friend, told the court that after the party Regan decided he did not want to go into town and was determined to walk home.
He refused to accept a ride home from Janet and Ian Dixon, the parents of another friend, even taking a swing at Mr Quinn in Frederick St as he attempted to get Regan into the car.
Mr Quinn went across the road and sat down after that.
"That was the last time I saw Regan."
Regan's body was found by men working on the Fryatt St wharf the next morning.
He was fully clothed, in the same clothes he had been wearing the previous night, but missing his watch, which he had been wearing at the party.
Visibly upset, Mrs Dixon allowed a constable to read her statement, in which she said the couple dropped Regan's friends off in town and then went back for Regan.
"He wouldn't get in and the last thing he said to us was "leave me alone, Ian; I'm fine and I'm going home".
Port Otago security guard David Jordan and a member of the public, Cheyenne Tairi, told police they both visited the Fryatt St wharf between midnight and 1am on July 10, but neither saw or heard anything unusual.
Police could locate no-one who saw Regan after 12.35am and he failed to answer his phone at 2am.
Marine search and rescue specialist Rowan Leck said he examined the wharf and harbour area, including a ladder from the water to the wharf, near where Regan's body was found, on July 11.
The area was badly lit, which meant it was a stroke of fortune that Regan had found the ladder.
However, he believed because of the way the ladder was constructed, Regan would have been unable to climb the ladder to the wharf.
Mr Leck also gave evidence on the potentially extreme effects cold water could have on a person who fell in.
The McCormacks said it was hard for them to accept Regan accidentally fell in the water.
If he had, they believed he would have been able to get himself out.
Mr McCormack said he had employed divers to search the bottom of the basin to find his son's watch, but the search was unsuccessful.
"They told me if it was there, they would have found it."
There were also unanswered questions about marks on his son's body and large, racist graffiti that appeared five weeks after his death, near the ladder where Regan was found.
Mrs McCormack said she discovered the "horrifying" graffiti and believed its was related to Regan's death.
"We want closure. It's the not knowing [what happened] that's so hard. He was a special kid. He had so much to give."
