Ernst & Young's investigation specialist, Jonathan Middup, has warned company executives to take results manipulation far more seriously.
It follows the conclusion to last week's groundbreaking case involving the Financial Services Authority and the former boss of AIT Group.
The three-month trial was the first contested criminal prosecution brought by the FSA under the Financial Services and Markets Act.
Carl Rigby, former chairman and chief executive of AIT Group, an AIM listed software company, was accused of fraudulently manipulating the company's results and when sentenced in October, could face up to a maximum of seven years' imprisonment.
Commenting on the judgment, Mr Middup said: "Before the conclusion of this landmark case, manipulating results had been regarded as less serious than theft, perhaps passed off as 'profit smoothing' or 'provision management'.
"This ignores a significant risk as the sums of money involved are often larger and the effects on investor confidence can be devastating - AIT's shares fell by 80 per cent when it adjusted its forecast."
Mr Middup cited a recent Ernst & Young investigation to highlight the weakness that existed before last week's conviction, involving a Midlands manufacturer.
He said: "A sales team booked fictitious customer orders to trigger their commission, but because the incentives were clawed back when the debts weren't paid the team had to keep increasing the amount of fraudulent sales at each quarter end. By the time we were called in, fictitious sales accounted for 70 per cent of revenue.
"Although our investigations had resulted in the sales team manager being caught red handed, he was allowed to leave with a clean reference. Overall, the board's reaction was muted and apart from new guidance issued to the sales team, no further action was taken."
Mr Middup said the judgment signalled a tougher line being taken by the FSA. He added: " The practice of sweeping these incidents under the carpet is no longer an option."
