Why Criminal Defence Lawyers Use Forensic Accountants

In financial crime cases, the prosecution has forensic accountants. HMRC has them. The NCA has them. The SFO has an entire department of them. If the defence doesn't have equivalent forensic expertise, it's at a serious disadvantage. Criminal defence forensic accountants analyse the Crown's financial evidence, identify errors and alternative explanations, and present the defence's case on matters of financial fact.

This page explains how forensic accountants support criminal defence solicitors across fraud, money laundering, tax evasion, and confiscation proceedings - and why early instruction makes a material difference to outcomes.

Why criminal defence solicitors need forensic accountants

Financial crime prosecutions are built on financial evidence. The Crown's case will typically include schedules of transactions, bank statement analyses, calculations of alleged proceeds, and a narrative tying the financial evidence to the alleged offending. This material is usually prepared by forensic accountants working within HMRC, the NCA, the SFO, or specialist police units.

The prosecution's financial analysis isn't always right. Assumptions are made. Alternative explanations are overlooked. Legitimate transactions are lumped in with suspicious ones. Benefit calculations are inflated. Without a defence forensic accountant to scrutinise this evidence, the defence team is relying on advocates alone to challenge detailed financial schedules under cross-examination. That's not enough.

A defence forensic accountant brings several things to the case:

• Technical scrutiny. They can identify errors in the prosecution's calculations, challenge assumptions, and test the methodology used to arrive at the financial figures.
• Alternative explanations. Financial patterns that look suspicious at first glance often have innocent explanations. Cash deposits might come from legitimate savings, not criminal proceeds. A lifestyle analysis might overstate expenditure by including business expenses. The forensic accountant presents these alternatives with supporting evidence.
• Independent expert evidence. The defence can call its own forensic accountant as an expert witness to present an alternative analysis to the jury. In complex financial cases, this expert evidence can be the difference between conviction and acquittal.
• Pre-trial representations. A forensic accountant's analysis can support representations to the CPS that the financial evidence doesn't support the charges. This can lead to charges being dropped or reduced before trial.

Types of criminal cases requiring forensic accounting

Forensic accounting is relevant across a broad range of criminal cases involving financial evidence.

Fraud (Fraud Act 2006). Fraud by false representation (s.2), fraud by failing to disclose information (s.3), and fraud by abuse of position (s.4). In each case, the prosecution must prove dishonesty and intent. The forensic accountant analyses the financial transactions to determine whether they are consistent with fraudulent intent or whether innocent explanations exist.

Money laundering (Proceeds of Crime Act 2002). The laundering offences under ss.327-329 POCA 2002 require the prosecution to prove that the property in question represents the proceeds of crime. A forensic accountant can demonstrate that funds have legitimate sources - employment income, savings, family loans, business profits - undermining the prosecution's contention that they are criminal proceeds.

Tax evasion (Criminal Finances Act 2017, Taxes Management Act 1970). Criminal tax prosecutions require proof of dishonesty, not just underpayment. A forensic accountant can demonstrate that under-declarations resulted from poor record-keeping, reliance on bad advice, or genuine error rather than deliberate evasion. Where the criminal allegation involves tax, our tax specialists at mtd.digital work alongside the forensic team to address both the criminal and technical tax aspects.

Bribery (Bribery Act 2010). Bribery cases involve tracing payments, analysing company accounts for hidden commissions, and examining procurement records. The forensic accountant can identify whether payments characterised as bribes by the prosecution were in fact legitimate commercial transactions.

False accounting (Theft Act 1968, s.17). Prosecution alleges that accounting records were falsified. The forensic accountant examines the records, the audit trail, and the accounting system to determine whether discrepancies result from deliberate falsification or from errors, system issues, or poor accounting practices.

Insolvency-related criminal offences. Fraudulent trading under s.993 Companies Act 2006 and offences under the Insolvency Act 1986 (including concealment of property, falsification of the books, and fraudulent disposal of property) all require forensic analysis of the company's financial records.

Challenging the prosecution's financial evidence

The defence forensic accountant's primary task is to subject the prosecution's financial evidence to rigorous scrutiny. This involves several layers of analysis.

Checking the arithmetic. Basic but essential. Prosecution schedules sometimes contain calculation errors, double-counting, or incorrect totals. In large cases with thousands of transactions, even small errors per transaction can produce materially different totals.

Testing assumptions. The prosecution's analysis relies on assumptions - about what constitutes a "suspicious" transaction, about the defendant's income sources, about business revenue. The forensic accountant tests each assumption against the available evidence. Are the prosecution's assumptions reasonable, or are they selecting the interpretation most adverse to the defendant?

Source of funds analysis. In money laundering and confiscation cases, the prosecution may assert that the defendant's assets represent criminal proceeds. The forensic accountant traces the defendant's legitimate income, savings, inheritances, and other lawful sources to demonstrate that the assets can be explained without reference to criminal conduct.

Lifestyle analysis review. HMRC and the NCA often prepare lifestyle analyses comparing the defendant's declared income against their estimated expenditure. These analyses can be overinflated - by including estimates rather than actual figures, by attributing joint expenditure solely to the defendant, or by double-counting items. The defence forensic accountant reviews the methodology and presents a corrected analysis.

Timeline reconstruction. The prosecution may attribute transactions to the alleged offending period when they actually pre-date or post-date it. The forensic accountant reconstructs the timeline from primary documents - bank statements, invoices, contracts - to show which transactions fall within the relevant period and which don't.

Confiscation proceedings under the Proceeds of Crime Act 2002

Confiscation proceedings under POCA 2002 take place after conviction. They are a separate hearing, and the stakes are high. The confiscation order determines how much the defendant must pay, and failure to pay can result in a default sentence of imprisonment.

The confiscation calculation has two elements:

The benefit figure. The total value of the defendant's benefit from criminal conduct. In "criminal lifestyle" cases (where the defendant has been convicted of a qualifying offence and meets the statutory conditions), a "lifestyle assumption" applies: all property received by the defendant in the 6 years before proceedings is assumed to be the proceeds of crime, and all property held by the defendant is assumed to have been obtained through criminal conduct. These assumptions are rebuttable - but the burden is on the defendant to prove that the property has a legitimate source.

The available amount. The total value of the defendant's realisable assets at the time of the confiscation hearing. The confiscation order is the lower of the benefit figure and the available amount.

The benefit figure can be far higher than the actual loss caused by the offending. If a defendant processed GBP 5 million through their bank accounts over 6 years - including legitimate salary, rental income, and business profits - the prosecution may claim the entire GBP 5 million as benefit unless the defendant can prove legitimate sources.

This is where defence forensic accountants make their greatest impact. They analyse the defendant's financial history, trace legitimate income sources, demonstrate that property was acquired lawfully, and challenge the prosecution's benefit calculation line by line. Reducing the benefit figure by even 20% can save the defendant hundreds of thousands of pounds and reduce or eliminate a default sentence.

Forensic accountants also help defendants apply for variations to restraint orders. Under a restraint order, the defendant's assets are frozen pending confiscation proceedings. But the defendant is entitled to apply for reasonable living expenses and legal fees. Demonstrating what is reasonable requires detailed financial analysis - showing the court the defendant's regular commitments, household costs, and the distinction between tainted and untainted assets.

Forensic accounting in serious fraud trials

SFO investigations and large-scale fraud trials present particular challenges for forensic accountants. The document volumes are enormous - millions of pages of financial records, emails, contracts, and corporate filings. The financial structures may involve multiple jurisdictions, shell companies, and nominees. The trial may last months.

The defence forensic accountant's role in these cases extends beyond number-checking. They help the defence team understand the financial evidence, identify the prosecution's strongest and weakest points, and develop the defence strategy on financial matters. This often involves:

• Creating simplified schedules and timelines that present the financial evidence in a way a jury can follow
• Identifying transactions that the prosecution has characterised as fraudulent but which have legitimate commercial explanations
• Analysing the defendant's role in multi-party cases to distinguish their conduct from that of co-defendants
• Preparing demonstrative exhibits that explain complex financial flows visually

In an SFO case, the forensic accountant may also need to deal with material obtained under compulsory powers (s.2 Criminal Justice Act 1987). This material can include answers to questions that the subject was legally compelled to provide. The defence forensic accountant must understand the restrictions on how this material can be used and ensure the defence strategy accounts for it.

Forensic accounting expertise is essential in these trials. A jury trying a complex fraud case is being asked to understand financial structures, transaction flows, and accounting concepts that may be entirely unfamiliar to them. The forensic accountant who can distil this into clear, understandable evidence provides an invaluable service to the defence - and, ultimately, to justice.

Giving expert evidence in criminal proceedings

Expert evidence in criminal proceedings is governed by Criminal Procedure Rules Part 19 - not CPR Part 35, which applies in civil and family proceedings. The duties are similar (the expert's overriding duty is to the court), but the procedural framework differs.

Under CrPR Part 19:

• The expert must provide a report that sets out their qualifications, the facts and assumptions relied upon, their methodology, and their conclusions
• The report must contain a statement that the expert understands their duty to the court and has complied with it
• The court may direct the experts to discuss the issues and prepare a joint statement
• The expert's report is served as evidence in chief; oral evidence focuses on clarification and cross-examination

Admissibility can be challenged. The defence (or prosecution) may argue that the expert evidence is not admissible because the expert lacks the necessary expertise, the evidence is not sufficiently reliable, or the issue is one the jury can decide without expert assistance. The forensic accountant must be able to demonstrate their qualifications and experience and explain why expert evidence is needed on the financial issues.

Giving oral evidence in the Crown Court is demanding. The jury may have been sitting through weeks of complex evidence. The forensic accountant must be clear, concise, and patient. They must answer the question asked - not the question they wish had been asked. And they must maintain their independence throughout, even when the advocate's questions are designed to push them towards a particular answer.

Early instruction: why timing matters

In criminal cases, timing matters more than in civil proceedings. The earlier a forensic accountant is instructed, the more they can do.

Pre-charge. If the forensic accountant is instructed before the suspect is charged, their analysis can support representations to the CPS. If the financial evidence doesn't support the charges - because the prosecution's figures are wrong, because there are legitimate explanations, or because the amounts don't meet the threshold for prosecution - the CPS may decide not to charge. This is the best possible outcome for the client.

Bail applications. In financial crime cases, the prosecution may oppose bail on the basis that the defendant has access to substantial assets and is a flight risk. A forensic accountant's analysis of the defendant's true financial position - showing, for example, that the apparently large bank balances are business funds, not personal assets - can support the bail application.

Document review. In large fraud cases, the prosecution may serve tens of thousands of pages of unused material alongside the evidence bundle. The forensic accountant can review this material efficiently, identifying documents that support the defence case and flagging material that should have been served as evidence.

PCMH and case management. Early forensic input helps the defence team engage constructively with case management hearings. The forensic accountant can advise on what expert evidence is needed, what documents should be requested, and what issues can be agreed or conceded.

Late instruction - after the evidence has been served and the trial date set - puts the forensic accountant under pressure and limits what they can achieve. In complex financial crime cases, the forensic accountant may need several months to review the prosecution's evidence, conduct their own analysis, and prepare a report. Instructing early gives them the time to do the work properly.

If you're a defence solicitor with a financial crime case - whether it's fraud, money laundering, tax evasion, or confiscation proceedings - instruct our defence forensic team as early as possible. Jack Ross Chartered Accountants has experience supporting defence teams in Crown Court fraud trials, POCA proceedings, and HMRC criminal investigations.