05/04/2016 12:50 PM AEST | Updated 15/07/2016 12:51 PM AEST

John Howard In Favour Of Second Gun Amnesty

Former Prime Minister John Howard has told the son of a shooting victim he is in favour of a second gun amnesty and current gun laws are not adequate to protect people.

Responding to a question from Alpha Cheng, the son of murdered police accountant Curtis Cheng, on SBS' Insight Programme, the former prime minister said current gun laws are not adequate.

Howard also worries the gun laws are "fraying at the edges".

'I am asked tonight would I favour it, yes,' John Howard answers questions about a second gun amnesty

Curtis Cheng, 58, was leaving work at Paramatta police station on October 2 when he was shot in the back of the head by 15-year-old Farad Jabar. Jabar was later shot dead by police.

"Almost certainly the answer to that question is no, the laws are not adequate," Howard said.

"I would have thought that everybody would agree that if 15-year-olds get weapons like that then there is something wrong with the laws.

"I am wholly against any watering down of the existing laws and I would encourage sensible strengthening of the current laws."

Howard introduced a national gun amnesty and tough gun restrictions in 1996, shortly after gunman Martin Bryant murdered 35 people at Port Arthur in Tasmania.

It is not the first time Howard has commented on the watering down of domestic gun laws, and last month he waded into the ongoing debate over gun control in the U.S.

The laws will never eliminate gun crime but can reduce it, Howard said.

"Once you give people access to weapons and those people snap or exhibit a mental illness then you will have tragedy," he said.

"I don't object (to an amnesty) at all... I think they work better when they are done nationally."

But he said he had not spoken to current Prime Minister Malcolm Turnbull about it.

"I am asked tonight would I favour it, yes, but that doesn't mean I have been campaigning for it," he said.

Howard was joined by survivors of the Port Arthur massacre, Australians whose loved ones have been killed by firearms and politicians including those from the pro-gun Shooters and Fishers party. The conversation on the program was heated, with gun lobbyists urging parts of the laws to be repealed which left Carolyn Loughton enraged.

You can watch that here:

In a comment piece for Fairfax media, Alpha Cheng on Tuesday said tighter gun laws could have saved his dad.

"There is widespread belief that the gun control measures introduced post-Port Arthur largely eradicated illegal guns in Australia," he said.

"I certainly believed that our gun policies would have prevented a 15-year-old from illegally accessing a .38 Smith & Wesson revolver. This was clearly not the case."

Alpha Cheng with his father Curtis, outside Parramatta police headquarters in October last year.

Cheng said after hearing the views of pro gun advocates, he recognised the need for "pragmatic gun laws for recreational users, sport shooters and people living on the land".

"However, this should not, and I believe it does not, contradict the need for tightening gun policy to prevent guns from being obtained illegally or for illegal means," he said.

Australia will mark 20 years since the Port Arthur massacre on April 28.

The killing spree stands as the worst in the nation's history and one of the bloodiest committed by a lone gunman in the world.

Then Prime Minister John Howard, wearing a bullet proof vest, addresses a pro-gun crowd in Sale in 1996

The success of Australia's gun laws has been heavily debated in the United States, where there is a constitutional right to bear arms and a huge public outcry over gun deaths and violence.

In November last year Liberal Democrat senator David Leyonhjelm appeared in a U.S. National Rifle Association propaganda video and declared his homeland "a nation of victims" because of its strict gun laws.

On the program Howard said those now in power "have to say no when the change that is being demanded is unreasonable" and the former prime minister counts gun reform as one of his greatest achievements in the top job.

"I put them in the absolute top rank because I believe very strongly that they have made Australia a safer country. Not the safest country in the world but they have made a contribution," Howard said.

"People talk a lot about human rights, talk often too much about it... The greatest human right we have is to walk unmolested and be free from arbitrary attack or murder. That's the greatest human right of all.

"People complained to me about some of the anti-terrorism laws I introduced. I always threw that back at them. I never really got a satisfactory repost to that because in the end the right to go unmolested and safe and secure from an attack or arbitrary murder is just so fundamental to our existence and anything that a Government can do to make that more likely, it ought to do."

This story has been updated to include further commentary from John Howards.