Pharmacy review as expert evidence

How medication expertise strengthens legal arguments and expert testimony

Published: 2026-04-03

Introduction

In litigation and formal dispute resolution processes, expert evidence plays a decisive role in establishing causation, liability, and damages. Within medication-related claims, pharmacist-led medication reviews provide objective, clinically rigorous expert evidence that illuminates prescribing decisions, medication interactions, and therapeutic appropriateness. This evidence is increasingly integral to insurance claims disputes, workers compensation litigation, and CTP matters across Australia and New Zealand.

The role of expert evidence in medication disputes

Disputes involving medication often turn on technical questions that fall outside the knowledge of generalist decision-makers: Was the prescribed medication appropriate for the condition? Were there safer alternatives? Did the medication regimen contribute to adverse outcomes? These questions require expert opinion from a qualified pharmacist.

Legal framework for pharmacist expert evidence

In Australian and New Zealand courts, expert evidence is admissible if the expert is sufficiently qualified and the opinion is within their field of expertise. Pharmacists, particularly those with specialised credentials and experience in clinical practice, readily meet this threshold. Their evidence is admissible on matters including medication interactions, adverse effects, prescribing guidelines, and deviations from accepted practice standards.

Key areas where pharmacy expert evidence strengthens legal arguments

Causation and medication safety

One of the most common uses of pharmacist expert evidence is establishing causation in adverse event litigation. Did the prescribed medication cause or contribute to a claimant's injury? A pharmacist expert can review the medical record, assess the temporal relationship between medication initiation and adverse events, identify known adverse effects, and opine on whether causation is established on a balance of probabilities.

Prescribing deviation and standard of care

In professional negligence claims involving prescribers, expert evidence on standard of care is essential. A pharmacist expert can analyse whether the prescribing decision complied with relevant guidelines, regulatory standards, and accepted practice. They can identify contraindications, inappropriate dosing, and failure to monitor that deviated from the accepted standard.

Medication interactions and polypharmacy

Complex medication regimens in chronic disease or multimorbidity cases often involve significant drug-drug and drug-disease interactions. Pharmacist experts can systematically analyse regimens, identify clinically significant interactions, and opine on whether the prescriber should have identified and managed these interactions.

Appropriateness of medication selection

For claims involving treatment decisions, pharmacist expert evidence can establish whether evidence-based alternatives existed that would have been more appropriate, safer, or less likely to cause adverse outcomes. This directly bears on questions of prescriber negligence and causation of injury.

Preparing pharmacy expert evidence for litigation

Expert evidence in legal proceedings must meet strict requirements. Experts have a duty to the court to provide impartial, truthful evidence. This requires careful documentation of the expert's methodology, qualifications, reasoning, and assumptions.

Distinguishing expert opinion from advocacy

A critical vulnerability in litigation is when expert evidence blurs into advocacy for one party's position. Courts actively scrutinise expert evidence for bias. To maintain credibility and admissibility, experts must:

• Acknowledge uncertainty: Where expert opinion is uncertain or contested, the expert should acknowledge this rather than present a position as definitive if it is not.
• Consider alternative explanations: Good expert evidence addresses alternative explanations for the facts and explains why they are less likely. One-sided analysis suggests advocacy rather than impartial expertise.
• Distinguish standard from deviation: When opining on standard of care, the expert should clearly distinguish what the standard was at the relevant time and where the prescriber deviated, rather than characterising all decisions differently from the expert's preference as negligent.
• Separate causation from speculation: The expert must base opinions on causation on established temporal relationships, known pharmacology, and clinical reasoning, rather than inference or suspicion.

Practical examples of pharmacy expert evidence in disputes

Workers compensation claim: Medication-related injury

A claimant alleges they suffered a serious adverse event (hepatotoxicity, renal impairment) caused by a prescribed medication. The pharmacist expert reviews the medical records, prescribing history, laboratory results, and known adverse effect profile of the medication. The expert can opine on whether the adverse event is a recognised effect, whether timing suggests causation, and whether the prescriber should have anticipated the risk and monitored for it.

CTP matter: Drug-drug interaction and breach of duty

The defendant prescriber initiated a new medication without reviewing the claimant's existing regimen. The claimant suffered an adverse event attributable to a significant drug-drug interaction. The pharmacist expert can establish that the interaction was contraindicated, widely known to the profession, and that the standard of care required checking for interactions before prescribing.

Professional negligence: Failure to deprescribe

A claimant was maintained on a long-acting benzodiazepine for decades despite current guidelines recommending deprescribing. The pharmacist expert can opine that guidelines recommend gradual withdrawal in older adults due to increased risks of falls, fractures, and cognitive impairment. If the claimant suffered an injury linked to these risks, the expert can establish breach of the standard of care.

Strengthening your position with pharmacy expert evidence

If you are involved in a medication-related dispute or claim, early engagement with a qualified pharmacist expert can clarify the medication issues at stake and shape your litigation strategy. IMM's pharmacists are experienced in preparing expert evidence for litigation and dispute resolution, working with legal counsel to develop opinions that are clinically rigorous, legally defensible, and persuasive.