South Australian Attorney-General Michael Atkinson has stepped up his personal attack on video game campaigners, likening them to bikie gangs.

The gamers4croydon group is running a candidate for next month's SA election, demanding there be a R-18 classification for video games.

Mr Atkinson remains opposed and has told the ABC's Good Game program of threats made to him.

"About two o'clock in the morning I had a threatening note from a gamer shoved under my door," he said.

"I feel that my family and I are more at risk from gamers than we are from the outlaw motorcycle gangs who also hate me and are running a candidate against me.

"The outlaw motorcycle gangs haven't been hanging around my doorstep at 2:00 am, a gamer has."

Mr Atkinson holds a veto power on reviewing national classification laws and remains opposed to relaxing a ban on R-rated computer games.

"The reason that I think interactive games are different is that in interactive games the person playing is doing the actions and I therefore think it has a higher impact - impact has always been a consideration in censorship or classification, call it what you will," he told Good Game.

"I'm sure most people can distinguish the fantasy of a computer game from the reality, but it is the small number we know can't that leads to mass murder in American high schools and in Thailand ... led to a gamer playing out the fantasy of hijacking a taxi cab and murdering the driver. It happened," the Minister also told ABC Stateline in an interview back in 2008.

Mr Atkinson admitted his three sons disagreed with his view on games classifications.

Discussion

Even though a discussion paper on the classification issue has now been released, Mr Atkinson thinks it has shortcomings.

"It would have been a fairer and more accessible paper to the vast majority of society if it had included still images of the games about which there's an argument," he said.

"I think it's very hard for those members of the public who don't play games to relate to the debate."

Kat Nicholson is standing against Mr Atkinson in his Adelaide seat of Croydon at the March 20 poll.

"I really think Australia needs an R-18 classification. I believe it's better for parents, it's better for children because parents can better monitor the content that their children are accessing," she said.

"A lot of parents for example don't realise that games that should be R-rated are being MA-rated here and this is educating them, this is making them realise it needs to be changed.

"I believe adults have the right to make adult choices regarding this matter."