But the state opposition says it would consider the government's idea.

Attorney-General Brian Wightman discussed the concept at a Standing Council on Law and Justice meeting with other attorneys- general in Sydney on Friday.

Yesterday, he said Tasmania was committed to working to develop a national approach on the issue.

"Because of the way social media works, any effective response will need national consistency to ensure jurisdictional boundaries are not used to subvert court orders," he said.

Opposition justice spokeswoman Dr Vanessa Goodwin said the Liberals were very conscious of the need to ensure that people received a fair trial.

"If additional mechanisms are needed to try and ensure this, then of course we would look at them," she said.

But adjunct Professor Paula Swatman, of the University of Tasmania School of Computing and Information Systems, questioned how a new law would prevent people from publishing prejudicial material on social media.

"It will depend on how heavy the penalties were," she said.

"Because people are inclined to put things on Facebook or Twitter without thinking about it.

"Then they think, `Oh, I shouldn't have done that', and then they try to take it down.

"But by that stage, it's too late and it's been copied on."

Professor Swatman said cyberspace enabled people to access prejudicial content, even if its original source had been deleted.

"You can penalise the person who did it, but what about the people afterwards?" she said.

"The impact is there."

Professor Swatman said any new law would also have to be widely publicised to discourage potential offenders.

Mr Wightman said a National Policing Senior Officers Group had formed a working group to consider related issues for social media and the law.

Email: ctang@examiner.com.au