Most accounting students learn the five fundamental principles of professional ethics from a textbook. Integrity. Objectivity. Professional competence and due care. Confidentiality. Professional behaviour. You memorise them, you tick the box, you sit your exam. Done.
But ethics in accounting only really makes sense once you’ve seen what happens when those principles fail. Real companies. Real auditors. Real fines, prison sentences, and 28,000 jobs vanished overnight. The case studies that come up in your CIMA and ACCA ethics questions are not abstract — they are based on these exact scandals.
I’ve just published a long-form YouTube video breaking down three of the most catastrophic accounting scandals of the last 25 years: Enron, Wirecard and Carillion. Below is a quick written summary — and then the video itself, which goes deeper into each one. If you’re studying for OCS, MCS, SCS or any ACCA paper with an ethics component, this is the kind of material that sticks.
Before we dive into the scandals, here is the framework every CIMA and ACCA student is expected to know. The IESBA Code of Ethics for Professional Accountants sets out five fundamental principles that apply to every accountant in the world. ACCA and CIMA both build directly on this code.
Be straightforward and honest in all professional and business relationships.
Don't let bias, conflict of interest or undue influence override your professional judgement.
Maintain your knowledge and skill, and act diligently in line with applicable standards.
Respect information obtained as a result of professional relationships.
Comply with laws and regulations, and avoid any action that discredits the profession.
Now watch each one fail.
For six consecutive years, Fortune magazine named Enron “America’s Most Innovative Company”. By the end of 2000 the share price hit $83.13 and the market cap exceeded $60 billion. Six weeks later, Enron filed for what was at the time the largest corporate bankruptcy in US history.
The mechanism was relentless. CEO Jeffrey Skilling championed mark-to-market accounting on long-term energy contracts — booking the projected future profits as current income, before a single cent was received. CFO Andrew Fastow then engineered hundreds of Special Purpose Entities to hide $14 billion of debt off the balance sheet. Fastow personally enriched himself by $45 million along the way.
The auditor — Arthur Andersen — collected $25 million in audit fees and $27 million in consulting fees from Enron in 2000 alone. When senior technical partner Carl Bass objected to the SPE accounting, he was removed from the audit team. When the SEC began its formal investigation, lead audit partner David Duncan instructed his team to shred tons of audit documents. Andersen surrendered its CPA licences. 28,000 employees worldwide lost their jobs.
What failed: every single principle. Integrity at the CFO level. Objectivity at the auditor level (consulting fees). Professional competence and due care when SPE accounting wasn’t challenged. Professional behaviour when the documents were destroyed. Enron is the textbook case because it is the only modern scandal where all five principles fell simultaneously — and the regulatory response, the Sarbanes-Oxley Act of 2002, permanently changed how auditors operate.
In June 2020, Wirecard became the first DAX 30 company in history to file for insolvency. The trigger was a single fact: €1.9 billion — roughly a quarter of its entire balance sheet — simply did not exist.
The fraud ran for over a decade. Wirecard claimed to use “third-party acquirers” in Asia and the Middle East to process payments where it didn’t have its own banking licences. Half of its reported revenue between 2016 and 2018 came from this opaque outsourced network. The €1.9 billion was supposedly held in escrow at two banks in the Philippines. When Financial Times reporter Dan McCrum chased the supposed Asian business hubs, journalists found a quiet suburban house in one location, and a family transport business operating out of a rice shed in another.
EY had audited Wirecard since 2008 and issued unqualified audit opinions year after year. The fundamental failure was almost too simple to believe: EY relied on documents, spreadsheets and screenshots provided by a third-party trustee and Wirecard management itself, rather than directly confirming the cash balances with the supposed banks. The most basic audit procedure — direct confirmation — was not performed. Meanwhile, German regulator BaFin pursued the journalists and short sellers rather than investigating Wirecard.
What failed: integrity (CEO Markus Braun and management), objectivity and professional scepticism (EY accepting management representations at face value), and professional competence and due care (the failure to execute basic audit procedures). The lesson is uncomfortable: Wirecard happened in 2020, not 2001. The reforms after Enron did not prevent it.
In January 2018, UK construction giant Carillion entered compulsory liquidation. It had £29 million in cash against approximately £7 billion in liabilities. It maintained roughly half of the UK’s prisons, ran smart motorway traffic systems, supplied school dinners and managed facilities at NHS hospitals and MoD sites. 12,000 UK staff lost their jobs. The pension scheme deficit was around £590 million.
The accounting failures were textbook. Carillion recognised revenue on long-term construction contracts long before outcomes were certain, aggressively treating expected claims from clients as guaranteed revenue. To mask the cash shortfall this created, it used reverse factoring (supply chain finance) and classified the resulting amounts as trade creditors rather than short-term borrowings — flattering operating cash flow by £200 million in 2016 alone. Without this distortion, operating cash flow would have been negative £85 million.
KPMG had audited Carillion for 19 years. The Financial Reporting Council investigation covered the 2014–2017 audits and uncovered systemic failures. Most shocking: audit reports for 2016 were sometimes signed off six weeks before the audit work was complete. The FRC imposed an initial £30 million fine, reduced to £21 million for cooperation — the largest fine ever issued by the regulator at that time. Engagement partner Peter Meehan was banned from the profession for ten years. When questioned at a parliamentary joint committee, Labour MP Peter Kyle told a KPMG audit partner: “I wouldn’t hire you to do an audit of the contents of my fridge.”
What failed: professional competence and due care (the FRC said KPMG failed “to adhere to the most basic and fundamental audit concepts such as to act with professional scepticism”), objectivity (Carillion was a 19-year, lucrative client and the audit team accepted what management presented), and integrity (signing off reports before the work was finished). Carillion is the scandal that triggered the Kingman and Brydon reviews and the proposed UK audit reform — replacing the FRC entirely with a new regulator.
If you want to practise the exact ethical scenarios CIMA and ACCA examiners draw from cases like these, Practice Tests Academy has free study packages for both qualifications with realistic ethics-flavoured questions. Links at the bottom of this post.
Ethics questions in CIMA OCS, MCS and SCS — and in ACCA’s Audit and Assurance, Strategic Business Leader and Strategic Business Reporting — are not abstract memory tests. They are scenarios. You will be given a situation and asked: what is the ethical issue, which principle is at risk, and what should the accountant do?
The students who do well are the ones who can name the specific principle (integrity, objectivity, professional competence and due care, confidentiality, or professional behaviour), explain why it applies, and recommend a proportionate response. The students who struggle are the ones who write generic answers about “acting professionally”.
Watch the video above and you will start to recognise the pattern. Enron, Wirecard and Carillion are not random tragedies. They are templates. The same warning signs — auditor too cosy with the client, management under pressure to hit numbers, basic procedures skipped — recur across every audit failure of the modern era. Once you can spot the pattern in a real case, you can spot it in an exam scenario.
Three scandals is just the start. Patisserie Valerie. WorldCom. Tesco’s £326 million accounting scandal. Steinhoff. Toshiba. Each one carries its own ethics lesson — and each one would make a strong follow-up.
If this post and the video are useful — and if there’s appetite for a Part 2 — let me know. I’ve put a poll up on the YouTube channel so you can pick which scandal you most want to see broken down next. The one with the most votes gets made. No pressure, no promises — just direct input from you on what’s worth a deep dive.
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