More than seven years after Shane Barker was fatally shot at his home in Campbell Town, police continue to hunt for his killer.

His father Rob Barker said he hoped the current police review into the case would finally lead to closure for his family.

In 2009 when Mr Barker discovered his son had been murdered, the devastated father said he believed the case would remain unsolved.

However he said the current investigation was “very encouraging”.

“If I could have one wish granted, other than having Shane back, it would be to know who and why,” he said.

“It’s not fair to have to suffer for the rest of our lives and the killer is not suffering at all at the moment.”

Police reported this week that they “firmly believe” the killer is someone they have already spoken to during their investigations.

Inspector Glenn Frame said police believed it was a “planned attack”.

“There was motivation behind it, so it’s highly likely the offender knew Mr (Shane) Barker,” he said.

Mr Barker said the possibility of finding out his son’s killer was someone close to them “could be worse than not knowing”.

“We’ve thought all along it could be someone we know,” he said.

“And we just don’t know whether it will hurt more if we find that out, but we still just want to know.”

Inspector Frame said police were confident the increase in reward would assist in finding a resolution for the case.

“We will leave no stone unturned in an attempt to get closure for the family,” he said.

The reward to find Shane’s killer, announced by police on Monday, is the highest in Tasmania’s history.

Inspector Frame said police would be undertaking a large number of inquiries in relation to the case in the coming months.