The case R v Ferguson; R v Sadler, R v Cox of the three police officers Cox, Sadler, and Ferguson is one such case. Being in the drug squad, have made it easy for these officers to illegally sell drugs through street dealers who they have caught on the pretext that they were carrying out strategic investigations. In reality, the squad members were benefitting from the drug dealers through cash income, and the only way to justify their benefits was to check on their accounts. This was why the expertise of a forensic accountant, Curtin was necessary.
Although evidence of assumed expert opinions is not admissible in a court of law, in this case, the Court made an exception to accountant Curtins opinions based on the logic that if a person's financial statements were to be produced in court then an expert in the area must be produced to analyze it. However, the expert, the forensic accountant, should merely explain the evidence (which the jury could have interpreted themselves had they the training to do so) but should not influence the jury of its contents. This was why the accountant's evidence became admissible.
The court of appeal also allowed the evidence admissible if Curtin explained the process of arriving at the conclusions. Curtin has used standard accountants methodology as set by the Statement of Forensic Accounting Standards - APS 11. This Standard provides clear guidelines to its members how to seek and utilize financial data and present it incomprehensible manner. Two of the important requirements is that the accountant can only make assumptions about the past or future events or amounts in the absence of the amount. His assumptions should be reasonable under circumstances, and they were suitably qualified and disclosed.