Gordon Holmes said a murderer should only be considered for release at this stage if they have worked to reform their ways while in prison.
At present a person serving life for murder can seek a sentence review from the parole board after seven-and-a-half years.
Mr Holmes, a Limerick solicitor, said: “I think this is too short. It gives the prisoner an idea that we are thinking of temporary release for them, at that stage, when we are not. It is unfair on the prisoner as it builds up hopes which are dashed.
“The public feel there is far too much killing going on and we have to respond to that. If harsher measures are necessary, so be it.”
He said if a prisoner jailed for murder had to serve more time before he could apply for parole, it would bring it home that murder means long years in jail.
“The average sentence served for murder is now 17 years. I would think if a prisoner in for murder did everything right in prison, and there are people who realise the enormity of what they have done, I would think you could start to consider releasing them after 12 or 13 years.
“The idea that people convicted of murder are getting out of prison early is a complete public myth.
“I would regard a double-digit sentence as absolute minimum. I wouldn’t see even in the most extenuating circumstance a person getting early release unless they have served a minimum of 12 years.”
He said if a prisoner is released on remission, certain controls should be imposed.
“A prisoner who gets four years in prison will, with the 25% remission, get out after three years. But I think that for that remission period of one year they should be under some form of supervision when they get out. If they know a probation officer will be popping around to see them they are going to be more careful.”
Mr Holmes said he would be in favour of increasing the remission in sentences for non-violent crime, subject to supervision.
On mandatory sentencing for murder, Mr Holmes said he favours the system in England and Scotland, where a judge in imposing a life sentence sets out a minimum tariff-defined term in years.