Accreditation and Quality Systems in Wildlife Forensics

ISO/IEC 17025:2017 (the current version) applies to any testing laboratory regardless of what it tests. Its requirements fall into two categories: management system requirements and technical requirements. For a wildlife forensic laboratory, both categories present specific challenges that a lab working only with human biological material would not encounter in the same form.

The management system requirements are largely documentation: the laboratory must have written procedures for everything it does, a document control system so that only current versions of procedures are in use, an internal audit program, a corrective action system for non-conformances, and a process for complaints. These requirements are demanding in a small specialist laboratory where the same two or three analysts design methods, validate them, conduct casework, and write reports, but they are achievable and they are the baseline that makes external audit meaningful.

The technical requirements are where wildlife forensics diverges sharply from human forensics. Method validation, measurement uncertainty, competence assessment, and equipment calibration all have to be applied to methods that are often adapted from research contexts, for analytes (species DNA sequences, morphological features) that have no certified reference materials in the sense that clinical or environmental laboratories use the term. Building a compliant quality system requires documenting why the available validation evidence is sufficient, not just citing a kit manufacturer's data sheet.

The Society of Wildlife Forensic Scientists was formed in 2009 in direct response to the absence of professional standards specific to wildlife forensic practice. ISO 17025 covers laboratory quality in general terms; it says nothing about how to handle a seized pangolin scale, how to choose which gene region to sequence for a particular taxonomic group, or how to interpret a DNA barcode match when the database has gaps.

SWFS guidelines are practitioner documents written by working wildlife forensic scientists for the same audience. They cover the scope of wildlife forensic disciplines (morphological, biochemical, genetic, chemical), reporting standards that describe how to phrase conclusions in the context of database coverage and method limitations, and best practices for specific evidence types including hair and feather microscopy, DNA barcoding, and chemical analysis of organic products.

SWFS guidelines are not legally binding in the way that ISO 17025 accreditation is. Their influence operates through professional norms: labs that follow them produce reports that are harder to attack; labs that do not follow them are more vulnerable to methodological challenges. As the wildlife forensics field grows and more prosecutions are contested, the gravitational pull toward SWFS-aligned reporting is increasing.

In human forensic DNA analysis, method validation was done once, intensively, by large governmental laboratories with thousands of verified reference samples and millions of dollars of investment. The resulting kits are used globally, and the validation data behind them is published, tested independently, and accepted by courts worldwide. A wildlife forensic analyst cannot point to anything equivalent when presenting a species identification for a lesser-known taxon.

Validation for wildlife forensics means demonstrating, for the specific method and the specific taxon, that the method correctly identifies the target species (or population) and does not produce false positives from related or commonly encountered species. It means documenting sensitivity (minimum DNA input for reliable amplification), specificity (which other species cross-react), reproducibility across analysts and instruments, and the acceptable range of input material quality.

1. Design and scope
   Define the taxon or taxa the method will cover, identify the gene region or markers, and specify the sample types (fresh tissue, dried skin, hair, bone, processed product).
2. Sensitivity testing
   Determine the minimum quantity of target DNA that reliably amplifies. For processed or archived specimens, the relevant input may be much lower than fresh tissue.
3. Specificity testing
   Run the method against DNA from related species and commonly occurring non-target species to document false positive rates. For a tiger (Panthera tigris) assay, lion, leopard, and domestic cat DNA must be tested.
4. Reproducibility
   Run the same samples on different days, on different instruments, and by different analysts. Record inter-analyst and inter-run variation to establish the method's uncertainty.
5. Internal validation report
   Document all validation data in a written report. This becomes part of the laboratory's quality system and is available for disclosure in any case using the method.

A critical practical constraint is the availability of reference specimens for validation. Many CITES-listed species are protected, and obtaining tissue from multiple individuals of the target species and its close relatives requires permits, institutional animal collections, museum loans, or collaboration with wildlife managers. This is not a trivial barrier; it is one of the main reasons that validated wildlife forensic methods exist for relatively few taxa compared to the breadth of species in trade.

ISO 17025 requires laboratories to participate in external proficiency testing schemes relevant to their scope. In human forensic DNA, these schemes have existed for decades, run by bodies like GEDNAP in Europe or the College of American Pathologists in the USA. Wildlife forensics has developed its own proficiency testing programs more recently, driven by SWFS and by collaboration among the small number of specialist laboratories worldwide.

A typical wildlife proficiency scheme works as follows: an organising body prepares a set of blind samples, each consisting of tissue, a processed product, or a prepared extract from one or more species. Participant laboratories receive samples without knowing the identity and are asked to apply their standard identification methods. Results are returned to the organiser and compared against the correct answers. Participants receive individual performance reports, and aggregate results (without identifying individual labs) may be published.

The limited frequency and scope of wildlife proficiency schemes relative to human forensics is an acknowledged weakness. An analyst who is the only person in a laboratory conducting a particular type of analysis has limited external benchmarking, which is exactly the situation that proficiency testing is designed to address. Expanding the range of taxa covered by formal schemes is an active priority for SWFS and for international capacity-building programs.

Chain of custody for a wildlife specimen is more demanding than for a standard forensic exhibit because the item itself changes over time. Tissue degrades, skin dries or moulds, a frozen specimen loses DNA quality if the cold chain is broken, pollen disperses during handling, and a live animal can die in storage, all requiring contemporaneous documentation.

The chain of custody record for a biological wildlife specimen must therefore document not just possession transfers but also storage conditions at each stage. The standard requirement in an accredited laboratory is a log covering: date and time of receipt, condition on receipt, storage location and temperature, any sub-sampling with the quantity taken and by whom, and any observations about changes in condition over time.

Sub-sampling deserves particular attention. A single rhinoceros horn may be the only exhibit in a case, and every sub-sample taken for analysis reduces what remains. The laboratory must document each sampling event: the date, the analyst, the size and location of the sub-sample, the purpose (species ID, population assignment, chemical analysis), and how the remaining item was resealed and re-secured. In high-profile cases, the defence may request a portion of the original exhibit for independent testing, and the record must show that sufficient material was retained.

As of the mid-2020s, the global picture for wildlife forensic quality systems is one of genuine progress and genuine gaps. The NFWFL is fully accredited and has been for years. A small number of European and Australian laboratories hold ISO 17025 accreditation for wildlife forensic scope. But most countries with significant wildlife crime problems, and most laboratories that conduct wildlife identifications as a side activity of a general forensic lab, do not have accreditation for their wildlife methods and do not participate in wildlife-specific proficiency schemes.

• Validation backlog: many methods in routine use by laboratories in developing countries have not been formally validated for the species and sample types they are applied to. Results from these methods may be correct, but they cannot be documented as validated under ISO 17025.
• Reference material shortage: building and exchanging reference specimens for validation requires overcoming CITES permit barriers, which creates irony: the regulations designed to protect species from trade also impede building the forensic infrastructure needed to prosecute illegal trade.
• Single-analyst laboratories: many wildlife forensic laboratories in low- and middle-income countries are effectively one-person operations, which makes internal audit, cross-checking, and proficiency testing structurally difficult.
• Court acceptance variability: in many jurisdictions, courts accept wildlife expert evidence without scrutinising the quality system behind it, which reduces the immediate incentive for laboratories to invest in accreditation. As prosecution success rates and the monetary value of cases increase, that is changing.

The path forward involves three converging efforts: SWFS and international bodies continuing to develop and promote species-specific guidelines; capacity-building programs (several funded through UNODC and the CITES Secretariat) that help laboratories in high-biodiversity countries build toward accreditation; and increasing court expectations in major prosecution jurisdictions that drive demand for quality evidence from all parties in an international trafficking chain.