High profile defence lawyer Barry Hart charged a family $1000 an hour for legal representation but they found out about his fees only once they laid an official complaint, a tribunal has been told.

Mr Hart faces four charges brought by the Law Society's Standards Committee including charging "grossly excessive" legal fees of $35,000 in late 2008.

He is also alleged to have refused to disclose a file to the Standards Committee and to have employed a private investigator without telling him that his bill would only be paid if legal aid was granted.

The hearing, before a five-member panel of the Lawyers and Conveyances Disciplinary Tribunal, is sitting at the Auckland District Court for the next two days [EDS: finishes Wed].

Standards Committee lawyer Paul Collins said a QC who had looked at Mr Hart's billing, said it was "difficult to see how he could justify the fees".

All witnesses in the hearing have been granted interim name suppression.

Mr Hart is alleged to have charged the fees at $1000 an hour despite much of the preparation work being done by a junior lawyer who had been practising for only two months.

On one of the occasions the fees were charged for "waiting time in court".

Mr Collins said Mr Hart had exploited the family who did not know about legal procedures.

"The compelling impression is that of a seriously irresponsible approach to fee charging in which invoices were created with substantial sums in rounded figures without any reference at all to the actual work being undertaken or to the interests of the client or his family."

The tribunal also heard from the sister of Mr Hart's client. She said the family found out what the fees were for only once they complained to the Law Society.

"The money that we paid in accordance to the services we received and finding out that we were able to get legal aid ... We weren't advised that was a service for us."

She said the family had taken out a loan to pay for the legal fees.

She was also asked about evidence that Mr Hart had filed with the court where it is alleged the woman told Mr Hart that she wanted the best and did not go with legal aid because the family didn't want a "crummy lawyer".

The woman denied she ever said that. She said when Mr Hart asked her for cheques totalling $35,000, she thought "This is probably how it works."

Earlier, Mr Hart's lawyer Nigel Cooke had asked for an adjournment on the grounds that Mr Hart had chest pains, breathing difficulties and fatigue.

Tribunal chairwoman Judge Dale Clarkson said Mr Hart's illness was not so serious as to require hospitalisation.

"The tribunal holds grave concerns about Mr Hart's willingness to proceed in this hearing."

She said Mr Hart's medical certificate contained "very bald assertions" and the doctor who issued it had refused to appear before the tribunal to answer questions about it.

Judge Clarkson said the tribunal would use its ability as a quasi-inquisitorial panel, and would question the prosecution witnesses.

Mr Cooke said Mr Hart needed to defend himself.

"The consequences for the committee could well be very serious for Mr Hart and they are not matters he takes lightly."

Mr Hart is well known in legal circles and has represented high profile criminals, such as Antonie Dixon who attacked two women with a samurai sword and shot a man dead in 2003.

Another high-profile client was Joseph Martin Reekers, who later admitted killing Marie Jamieson and dumping her body behind a west Auckland factory.

- APNZ