The Law Society says sloppy invoicing by lawyers working within the legal aid system is not common, as claimed by the lawyer representing Chris Comeskey.
Mr Comeskey has been suspended from practising law for nine months after pleading guilty to three charges of professional misconduct.
At a hearing before the Lawyers and Conveyancers Disciplinary Tribunal, Mr Comeskey admitted three charges including misleading the Court of Appeal and overbilling the Legal Services Agency.
His lawyer, Russell Fairbrother, referred to a Government review which suggested there is widespread abuse of the legal aid system, and said sloppy invoicing is standard practice.
The Law Society says those allegations are untrue. The Criminal Bar Association says if Mr Fairbrother has knowledge of lawyers abusing the system he has an ethical obligation to inform the Law Society.
Meanwhile, Mr Fairbrother says his client will use his nine month suspension from the legal profession to get his business practices in order.
He told Morning Report that Mr Comeskey had trusted other people to run the business side of his practice, and the suspension will be a good time for him to get some better systems in place.
