The highest court in Singapore on Monday dismissed an appeal by general surgeon Susan Lim against her conviction on charges of professional misconduct over the amount she charged a patient from the royal family of Brunei.

In a 109-page written judgment, the three-judge Court of Appeal said Dr Lim's case was "clearly one of the most serious cases - if not the most serious case so far - of overcharging in the medical profession in the local context". The court dismissed her claims that she was justified and there was no ethical obligation to charge a fair and reasonable amount and pointed out her approach showed she had shown no remorse.

In the judgment, the court ruled there is an objective ethical limit on medical fees that operates outside contractual and market forces, The court found that, given a doctor's specialised knowledge and training, there arises an ethical obligation on the part of a doctor not to take advantage of his patient. And this ethical obligation to charge a fair and reasonable fee is not superseded by a valid agreement between the doctor and his patient, the court held.

In 2012, Dr Lim was found guilty of 94 charges of professional misconduct by a Singapore Medical Council (SMC) disciplinary committee for charging about $24 million for the services provided to Pengiran Anak Hajah Damit Pg Pemancha Pg Anak Mohd Alam for 110 treatment days from January to June 2007. Dr Lim was then given a three-year suspension and fined $10,000 - which was upheld by the appeal court.