Earlier this month, the South Australian government increased the court fee for the family or beneficiary of an estate to obtain probate by 18 per cent, from $841 to $995. The Law Society has likened this increase, on the back of a 25 per cent increase in 2008-09, to a death tax that would target vulnerable members of the community.

"Death duties were abolished in 1979," Law Society president Ralph Bönig said. "The massive increase in court probate fees without any of that money being returned to the court is nothing more than death tax by the backdoor".

Bönig said that it was likely that the extra revenue collected by the fee increase will disappear into a "black hole", as the state's 2011-12 budget did not allocate any extra finding to the courts.

The South Australian government has come under intense criticism from legal groups in recent weeks after it flagged it would deny accused persons who successfully defend police prosecutions their costs.

The South Australian president of the Australian Lawyers Alliance, Anthony Kerin, said such a move would threaten to undermine the rights of all citizens.