They are one of the big four accounting firms. Government agencies and major corporations trust them to audit their books and ensure everything is above board.So what happens when one of these auditors is accused of a catastrophic failure of integrity?KPMG will face this question and many others when it fronts a Senate inquiry this week. The explosive claims emerged after a whistleblower brought allegations the firm misused confidential client data to potentially win business with other companies.Today, senior business reporter Colin Kruger explains why this scandal extends well beyond the big end of town and might affect anyone with an investment or super fund.Subscribe to The Age & SMH: https://subscribe.smh.com.au/See omnystudio.com/listener for privacy information.