A man jailed over a one-punch attack that killed teenager Patrick Cronin has failed his second bid to reduce his eight-year sentence.

Andrew William Lee pleaded guilty to manslaughter after striking Mr Cronin, 19, outside the Windy Mile Hotel at Diamond Creek in 2016.

A relieved Matt Cronin, Patrick’s father, spoke to Neil Mitchell after the ruling.

He was happy with the court’s decision, but said it does highlight the need for tougher punishment for coward punch attackers.

Lee was sentenced to eight years in jail, with a five-year minimum.

“So he’s now got less than four years to go and he’ll be walking the streets, no doubt, because I don’t think anyone ever does the full term,” he said.

“They only seem to serve the non-parole period, which is five years, which is pathetic.

“This is why we need to get these coward punch laws changed.”

Mr Cronin said the focus should be on the laws around one punch attacks.

“We’ve got a meeting tomorrow with our Victims of Crime Committee, so we meet the new Attorney-General tomorrow,” he told 3AW.

“So I’ll be having a good chat with (new Attorney-General) Jill Hennessy about the coward punch laws, and what we can do to change them.”

Click PLAY to listen