Bryant: 'Port Arthur wouldn't have happened if I couldn't get a gun'

Australia’s worst mass murderer Martin Bryant told police he would not have been able to carry out the massacre if weak laws at the time had not allowed him to buy his weapons with cash and without showing a gun licence.

Bryant, who shot 35 people dead and injured 23 others during a cold-bloodied rampage at Port Arthur in Tasmania on April 28, 1996, also revealed he practiced for the killings by shooting at trees in remote bushland – but refused to use bottles as targets because the broken glass could injure animals.

Last week, Bryant was seen laughing in chilling police interview videos that aired for the first time outside a courtroom on Seven's Sunday Night.

In more unseen footage, the killer described how easy it was to buy his arsenal of weapons, including a high-powered semi-automatic assault rifle from local gun dealer Terry Hill without a licence.

Detective: Did you make out you had a gun license (licence) when you purchased them?

Bryant: No, I never discussed it, never. I just said I had the cash on me and he said that's alright.

Detective: Did he ever, did he ask to see if you had a gun license (licence)?

Bryant: No, never.

Detective: So are you blaming Terry Hill for what happened?

Bryant: Well I'm not blaming anyone. It wasn't Terry Hill's fault. I got that one out of the paper don't forget. So you can blame the Mercury for advertising.

Bryant: If they don't advertise'em it wouldn't've happened.

Incredibly, Bryant also told of concern for wildlife as he planned the atrocity:

Bryant: I used to go to one spot

Detective: To shoot at trees.

Bryant: There's a forestry place there.

Detective: Used to shoot a few tin cans? Oh, right. Bottles?

Bryant: Bottles, no, not bottles, 'cause they break and they could injure animals.

The ease with which Bryant got his hands on semi-automatic assault rifles like the AR15 led the then-Prime Minister John Howard to push for tough new gun laws, banning ownership of such weapons.

In the US, the AR15 again made headlines again in 2012 when it was used buy a gunman at Sandy Hook Elementary School to kill 26 people including 20 children.

Despite overwhelming evidence, Bryant denied he killed 35 people for months. His lawyer John Avery revealed in an interview [hyperlink] that he eventually convinced Bryant to confess, using his pride against him.

But the killer's casual and even happy demeanor in the new videos has left many wondering if he was sane enough to stand trial.

The psychiatrist who evaluated Bryant — Paul Mullen — says he was not a madman.

"He’s dim, he’s angry, he’s resentful, he feels persecuted…He wants to revenge himself on the world, he wants to become famous."

"I mean all of those are disturbances… but none of them amount to serious mental illness."