The lawyer who represented Australia's worst mass murderer says he is still haunted by the experience two decades on.
Tasmanian lawyer John William Avery defended Martin Bryant after the Port Arthur massacre in April 1996.
As the 20th anniversary of the mass shootings nears, Mr Avery told the Seven Network's Sunday Night program there wasn't a day since the court case he hadn't thought about the killer.
"Let's hope that I can (shake him off) after this," he said of the interview.
Bryant eventually pleaded guilty to killing 35 people and was handed 35 life sentences.
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Years later Mr Avery would himself spend time behind bars, after pleading guilty to defrauding his clients of more than $500,000.
The day after Bryant was sentenced, Mr Avery sat in a dark office and recorded his thoughts.
"I thought I could easily walk away and get on with life, but I think perhaps that I have been touched by him like his victims," Mr Avery said in the recording.
"Why can't I get him out of my mind? And why do I continue to feel guilty that I can't feel that I hate him?"
Mr Avery said he felt more like a friend than a lawyer to the murderer.
"How could a client do this to me? How could someone rob me of myself?" he said in the recording.
Bryant had not shown any remorse and had wished he could kill more people, Mr Avery told the Sunday Night program.
In police interview footage following the killing spree, Bryant is seen laughing at the deaths and eagerly asking how many people had been injured.
The massacre inspired the tightening of national gun ownership laws by the Howard government.
