EMMA ALBERICI, PRESENTER: A law firm is facing more than 70 separate court cases over allegations it overcharged former clients, most of whom were accident victims, Keddies Lawyers, which has now been taken over by Slater & Gordon. Former Keddies partners have already paid back over a million dollars to former clients and there's speculation that the final bill could hit $10 million.

Lateline has obtained internal Keddies documents that shed light on some of their controversial billing practices, as Steve Cannane reports.

STEVE CANNANE, REPORTER: Law firm Slater & Gordon has a reputation for standing up for the underdog, representing victims of asbestos, thalidomide and tobacco. But last year when they bought Keddies Lawyers for $35 million, they acquired a firm mired in allegations of over-charging the most vulnerable.

PAUL HENNESSY, FORENSIC ACCOUNTANT: It's the most disreputable I've seen in a career that stretches back almost 50 years. It's the worst professional behaviour by far.

STEVE CANNANE: Keddies specialised in compensation law, no win, no fee cases for accident victims who struggled to afford legal representation.

KEDDIES LAWYERS TV ADVERTISEMENT (voiceover by Paul 'Fatty' Vautin): Keddies has been protecting people's rights for nearly 30 years. They specialise in compensation law. It's all they do.

STEVE CANNANE: But now Keddies partners are facing a number of court cases over claims of over-charging.

STEPHEN FIRTH, FIRTHS LAWYERS: They've already paid back to our clients in excess of a million dollars and we've still got a long way to go. ... It may be close to $10 million by the finish.

STEVE CANNANE: Stephen Firth is representing around 100 former Keddies clients. He says there are even examples of Keddies lawyers billing for more than 24 hours in a single day.

STEPHEN FIRTH: I think the record is we saw one solicitor claim he had spent 33 hours in one matter on one day, which can't be right.

STEVE CANNANE: Mohammed Tariq took to the streets to protest his Keddies bills.

MOHAMMED TARIQ, FORMER KEDDIES CLIENT: We travelled to city, which is Goulburn Street, which is 1.8 kilometres from Redfern to Goulburn Street and Keddies Lawyers charged me $600 for the trip. A cheque was sent to me by the insurance company for the sum of $227.55 and the Keddies charged me $245 to release that cheque.

STEVE CANNANE: These examples of overcharging were picked up in itemised statements like this one. But Lateline has obtained internal Keddies emails that show that bills blew out well beyond what was itemised at settlement.

This Keddies result form shows that the WIP, or work in progress, was $200,000 at the settlement of the case, but the final bill was nearly $380,000.

Forensic accountant Paul Hennessy has represented around 20 former Keddies clients.

PAUL HENNESSY: Typically, the memorandum of costs will follow the accumulation of the work in progress. In my experience, it's most unusual to see an uplift of the type shown as per those schedules.

STEVE CANNANE: Lateline has cross-checked 12 separate Keddies results forms. In each case the itemised bill increased significantly; in four instances by over $100,000 each. Lateline has also obtained an email that shows Keddies founder Russell Keddie instructing his solicitors on ways they can "value add", as he puts it, to their client's bills.

RUSSELL KEDDIE, FORMER KEDDIES PARTNER (excertp from email, male voiceover): "Would you all mind adding 12 units at partners rates for 'Analysis of and Considering Strategy' to all those matters that a Partner responds to you and adds an issue or two. Thanks - we should be rewarded for the brainstorming ...".

STEPHEN FIRTH: Well, Steve, what this tells you is that the partner is directing - that's Russell Keddie - is directing his solicitors that whenever they discuss any client's matter with one of the partners they are automatically to record 72 minutes of time having been spent on that regardless of whether it took five minutes, 10 minutes or 20 minutes. 72 minutes was always to be logged to the client's account for that.

STEVE CANNANE: And at a partner's rate that would be quite high.

STEPHEN FIRTH: At the partner's rate, which might be $390, $400 an hour, perhaps more.

STEVE CANNANE: The three partners of Keddies were Russell Keddie, Scott Roulstone and Tony Barakat.

Former Keddies clients are frustrated by the lack of action taken against them by the Legal Services Commissioner.

MOHAMMED TARIQ: The Legal Services Commissioner has taken no action against Keddies. There has been so many complaints, but he has done nothing about it.

STEVE CANNANE: The Legal Services Commissioner in NSW has received dozens of complaints against Keddies. Just one of them has been referred to the Administrative Decisions Tribunal. That case has yet to be heard.

The commissioner would not address specific cases, but says it's difficult for him to deal with allegations of overcharging.

STEVE MARK, NSW LEGAL SERVICES COMMISSIONER: It is very difficult in our jurisdiction to kind of package all those complaints up which common sense would suggest you should and then run what would be called a course of conduct complaint in the tribunal. Those don't work. The tribunal looks at individual issues.

STEVE CANNANE: In one decision involving Keddies, the commissioner absolved a solicitor of responsibility because the firm's accountants had drawn up the bill.

NSW LEGAL SERVICES COMMISSIONER (male voiceover): "I am of the view that, as an employee, Mr Marocchi was entitled to rely on his firm's accounting systems ...".

STEVE CANNANE: The commissioner hopes new legislation will give him extra powers.

None of the former Keddies partners were available to talk on camera. One of them, Tony Barakat, provided the following statement:

TONY BARAKAT, FORMER KEDDIES PARTNER (male voiceover): "I am unable to comment on the information used to base the Lateline programme because of the matters that are pending to be heard in the Supreme Court and the ADT. As a consequence, the information used shows a one-sided version of events and contains many inaccuracies and half truths."

STEVE CANNANE: Slater & Gordon, who bought Keddies last year, were not available for comment. At the time of purchase, they said the deal represented a new line in the sand for Keddies and a new way of operating.

Steve Cannane, Lateline.