Advanced Audit and Assurance (International) · Specific assignments

Forensic Audit and Public Sector Assignments for ACCA AAA

Updated 11 October 2026 · Fact-checked

A forensic audit investigates a specific suspicion, such as fraud, to gather evidence that may be used in legal proceedings. A public sector audit also tests value for money: economy, efficiency and effectiveness. To answer, state the objective, then the procedures, evidence, reporting and risks, applied to the scenario.

Understand Forensic Audit and Public Sector Assignments

A statutory audit gives an opinion on whether financial statements are free from material misstatement. It uses sampling, materiality and a fixed annual cycle. It is not designed to find all fraud.

A forensic investigation starts from a specific concern: a suspected fraud, a loss, a dispute or a regulator's inquiry. The aim is to establish what happened, who was involved, how it was done and how much was lost. Evidence must be gathered so it can stand up in court or a disciplinary process. There is no materiality threshold in the same sense, and the scope is set by the engagement terms, not by the financial statements.

Forensic work needs care over evidence. Preserve originals, keep a chain of custody, take forensic images of computers and phones, and document everything. Interview people in a planned order, usually witnesses first and the suspect last. Follow local law on privacy, employment and self-incrimination. Use specialists such as IT forensics experts and lawyers. Keep the work confidential and agree who receives the report.

Public sector audit covers governments, agencies and bodies funded by taxpayers. The audit is broader than a financial opinion. It often covers regularity (spending was authorised and lawful), propriety (spending met standards of conduct) and value for money (VFM). VFM is judged on the three Es: economy (low cost for the quality needed), efficiency (best output for the inputs) and effectiveness (objectives achieved). Some bodies add equity or environment.

Public sector objectives are often not profit. This makes measuring success harder. Auditors need suitable criteria and indicators, and reports are often public and go to a legislature or oversight body. The auditor may also need independence from government under the local legal framework.

Key rules to remember

Value for money (the three Es): VFM = Economy + Efficiency + Effectiveness; Economy is about inputs and cost, efficiency about output per input, effectiveness about outcomes against objectives. Say which E each point relates to.
Efficiency measure: Efficiency = Outputs ÷ Inputs; For example, cases processed per staff member or cost per case. Compare with a benchmark or prior period.
Fraud triangle: Fraud = Pressure + Opportunity + Rationalisation; Use it to explain why fraud may have happened and where to look. It is a model, not a rule.
Forensic evidence discipline: Secure → Preserve → Document → Analyse → Report; A memory aid for the order of work. Not a formal standard.

How to solve Forensic Audit and Public Sector Assignments questions

Use this method for any question on forensic investigations or public sector assignments.

1Read the requirement and mark the verb: explain, discuss, recommend, evaluate or list. This sets the depth.
2Identify the assignment type: forensic investigation, fraud inquiry, regularity audit or VFM audit. State the objective in one sentence.
3Pick out scenario facts: who is involved, what is suspected, the amounts, the systems and the sensitive points.
4Set out the procedures. For forensic work cover securing evidence, interviews, data analysis, specialists and legal advice. For VFM cover criteria, data and benchmarks for each of the three Es.
5Link each procedure to a scenario fact. Do not give a generic list.
6Cover reporting: who gets the report, its purpose, the confidentiality limits and any duty to report externally.
7Add ethical and risk points: independence, competence, confidentiality, legal exposure and the engagement letter.
8Close with a clear recommendation or conclusion. Use a professional tone for the skills marks.

Quickest way: Objective, evidence, people, report

When to use it: Use when time is short and you need a structure in under a minute.

Write four headings: Objective, Evidence, People and Reporting.
Under Objective, state what the work must show (fraud facts or the three Es).
Under Evidence, list sources and how to protect them, with two scenario-specific items.
Under People, note interviews, specialists and ethical issues.
Under Reporting, note the recipient, the form and the legal limits. Then write in full sentences.

Common mistakes in Forensic Audit and Public Sector Assignments

Treating a forensic investigation as a normal audit with the same sampling and materiality.
Students rely on the familiar statutory audit approach.
Fix: State that the scope is driven by the suspicion and the engagement terms, and that evidence is gathered for legal use.
Saying the statutory auditor is responsible for finding all fraud.
Confusing the auditor's role with a fraud inquiry.
Fix: Say that management and those charged with governance are responsible for prevention and detection, and the auditor obtains reasonable assurance on material misstatement.
Listing the three Es without applying them.
Students memorise the definitions but not the use.
Fix: For each E, give a measure from the scenario, such as cost per unit or waiting time, and compare it to a benchmark.
Ignoring evidence handling, such as chain of custody and legal advice.
Focus is on finding the fraud, not on proving it.
Fix: Always mention preserving originals, imaging devices, documenting who handled items and taking legal advice before interviews.
Confusing economy and efficiency.
Both relate to cost and look similar.
Fix: Economy is the price paid for inputs. Efficiency is output obtained per unit of input. Effectiveness is whether the objective was met.

Worked examples

Example 1

A company suspects its purchasing manager has been approving payments to a fictitious supplier. The audit committee asks your firm to investigate. Explain the main steps you would take. (8 marks)

Show the solution

Objective: the engagement letter should set the scope, which is to establish whether fictitious payments were made, the amount, the method and who was involved. It should also state who receives the report.
Secure evidence: preserve supplier files, payment records and email. Image the manager's computer and phone with the company's consent and legal advice. Restrict access to the records.
Analyse data: match the supplier's bank details, address and tax number to employee records. Look for payments just below approval limits and missing delivery records.
Verify the supplier: confirm existence through registries and a site visit. Check for goods received notes.
Interviews: speak to witnesses such as accounts staff first. Interview the manager last, with legal or HR advice, and record the interview.
Use specialists: involve an IT forensics expert and a lawyer for admissibility and employment law.
Report: write a factual report to the audit committee, showing evidence and loss. Keep it confidential. Consider reporting to the police or regulator if law requires it.

Answer: Agree scope in writing, secure and preserve evidence, analyse payments and supplier data, verify the supplier, interview in a planned order with legal advice, use specialists, and report factually and confidentially to the audit committee.

Example 2

A government health agency wants a value for money audit of its ambulance service. Explain how you would assess economy, efficiency and effectiveness. (9 marks)

Show the solution

Set criteria first: agree with the agency what good looks like, such as target response times and cost benchmarks.
Economy: compare the prices paid for vehicles, fuel and staff to market rates or other regions. Check that tenders were competitive and that spare capacity is not paid for needlessly.
Efficiency: measure outputs per input, such as calls answered per crew hour and cost per call. Review vehicle downtime and dispatch delays. Compare with prior years and similar services.
Effectiveness: compare actual outcomes with objectives. Examples are the share of emergencies reached within target time and patient survival or satisfaction results. Check that the data used is reliable.
Consider context: rural areas may have longer times through no fault of management. Note the budget constraints.
Report: give findings by each E, with evidence and practical recommendations to the agency and the oversight body.

Answer: Agree criteria, then test economy through input prices and procurement, efficiency through output per input measures, and effectiveness through outcomes against targets. Allow for context and report evidence-based recommendations.

Exam tips

Always compare to the statutory audit when asked about differences: purpose, scope, materiality, evidence standard and reporting.
Tie every procedure to a fact in the scenario. Generic lists lose professional skills marks.
In public sector questions, name the E you are discussing and give a measure for it.
Mention ethics and confidentiality in forensic questions, including legal advice and engagement terms.
Use a clear structure with short headed paragraphs and end with a recommendation.

Practice questions from Specific assignments

Forensic Audit and Public Sector Assignments in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Forensic Audit and Public Sector Assignments: frequently asked questions

What is the difference between a forensic audit and a statutory audit?

A statutory audit gives an opinion on the financial statements using materiality and sampling. A forensic audit investigates a specific suspicion and gathers evidence that can be used in legal or disciplinary action. Scope, reporting and evidence handling are different.

What are the three Es in a value for money audit?

They are economy, efficiency and effectiveness. Economy is about the cost of inputs. Efficiency is output obtained per unit of input. Effectiveness is whether the objectives are achieved.

Does the statutory auditor have to find fraud?

No. Management and those charged with governance are responsible for preventing and detecting fraud. The auditor obtains reasonable assurance that the financial statements are free from material misstatement, including that caused by fraud, and responds to fraud risks.

Why is public sector audit different from private sector audit?

Public bodies are accountable for taxpayer money and often have non-financial objectives. The audit may cover regularity, propriety and value for money as well as the financial statements. Reports are often made public.