Challenging Expert Fees at Detailed Assessment

Expert evidence is frequently one of the largest disbursement elements in a bill of costs. At detailed assessment, expert fees are not automatically recoverable simply because an expert was instructed. Paying parties can, and often do, secure significant reductions where necessity, proportionality, or scope are not properly evidenced.

This article explains how expert fees are assessed, the common grounds of challenge, and the strategic approach paying parties should adopt.

The Legal Framework for Expert Fees

Expert fees are governed by the same core principles that apply to all costs:

• reasonableness

• necessity

• proportionality

Even where expert evidence was permitted, the amount claimed remains open to challenge.

The court will consider:

• whether expert evidence was reasonably required

• whether the discipline and number of experts were justified

• whether the fees claimed are proportionate to the issues in dispute

These issues sit within the wider question of recoverability and conduct.

Permission Does Not Equal Recovery

A common misconception is that where the court granted permission for expert evidence, the fees are automatically recoverable.

That is incorrect.

Permission establishes admissibility, not quantum. At detailed assessment the paying party may still argue:

• the expert’s hourly rate is excessive

• time spent is unreasonable

• work falls outside the permission granted

• the report deals with issues that were not live

This distinction is frequently overlooked and provides a strong basis for reduction.

Scope Creep and Work Outside the Letter of Instruction

One of the most effective paying party arguments is that the expert has undertaken work beyond the permitted scope.

Typical examples include:

• supplementary reports that were not ordered

• extensive liaison with solicitors or counsel

• work on issues that were later abandoned

• duplication between multiple experts

Where the work goes beyond the original instruction, recoverability becomes vulnerable.

This is particularly powerful when combined with detailed assessment paying party strategy arguments on necessity.

Proportionality and Expert Fees

Expert evidence must be proportionate to:

• the value of the claim

• the complexity of the issues

• the importance of the expert discipline

High expert fees in modest-value claims are a primary target for reduction.

Even if each individual item appears reasonable, the court may apply a global proportionality reduction, as explained in our guide to proportionality challenges at detailed assessment.

You cannot itemise your way out of disproportionality.

Duplication Between Experts and Legal Teams

Another common ground of challenge is overlap between:

• multiple experts in similar disciplines

• expert and counsel analysis

• expert and solicitor review work

Where the same material is analysed by several fee earners, the court may disallow part of the expert’s time.

This links directly to fee earner delegation challenges and the need for proper division of labour.

Hourly Rates and Market Testing

Expert hourly rates are not immune from scrutiny.

Paying parties should:

• compare rates with market norms

• examine the expert’s CV and specialism

• consider whether a lower-cost expert could have been used

Where the discipline is common and the issues straightforward, premium rates are difficult to justify.

Attendance at Conferences and Hearings

Expert attendance at conferences with counsel or at trial is often claimed as a disbursement.

Challenges commonly succeed where:

• attendance was not reasonably required

• multiple experts attended unnecessarily

• preparation time is excessive

These items must be justified by reference to the needs of the case, not convenience.

Practical Paying Party Strategy

Successful challenges to expert fees focus on:

✔ necessity of the expert discipline

✔ compliance with permission orders

✔ proportionality to claim value

✔ duplication and scope creep

✔ reasonableness of hourly rates

This forms part of a wider paying party detailed assessment defence and should be planned from the point the report is served.

Common Mistakes by Receiving Parties

Reductions frequently arise where:

• the letter of instruction is not disclosed

• time is block-billed

• the report addresses irrelevant issues

• multiple experts are used without justification

• fees are disproportionate to the sums in issue

These evidential gaps create clear opportunities for challenge.

Why This Matters for Paying Parties

Expert fees can represent a significant proportion of a bill. Targeted challenges often produce substantial savings.

Early analysis of:

• permission orders

• letters of instruction

• the scope of reports

allows paying parties to frame strong Points of Dispute and improve settlement leverage.

Key Takeaways

• Permission for expert evidence does not guarantee recovery of the fees claimed

• Proportionality is central to expert fee challenges

• Work outside the letter of instruction is vulnerable

• Duplication between experts and legal teams leads to reductions

• A structured paying party strategy can significantly reduce exposure.