Looking for a sports expert witness now? Our Sports practice sets out who we can put forward and how to request a shortlist.
What we looked at
The Court of Arbitration for Sport publishes a selection of its awards on its recent decisions page. In October 2026 the page listed 537 awards from 2018 to 2026, most of them from 2023 to 2025. We read 536 of them in full (one would not download). For each award we recorded the sport, the subject and whether the award records expert evidence: an expert report, an expert opinion or expert testimony. Where the award names the experts, we read the passages about them to record their field and which party called them.
One award in four involves expert evidence
125 of the 536 awards (23%) record expert evidence. That is lower than many practitioners expect, because most CAS appeals are about contracts, eligibility and disciplinary rules, where the facts are in the documents and the argument is legal.
Awards with expert evidence are also longer: a median of 35 pages, against 26 for those without, which reflects the extra issues experts bring.
Where experts matter most
- Doping: 61 of 118 awards (52%) involve expert evidence. Most contested doping cases turn on science: the source of a substance, the reliability of an analysis or the meaning of a biological passport profile.
- Integrity and match-fixing: about four in ten awards tagged with these subjects involve expert evidence.
- Governance and elections: 18%.
- Football transfers and contracts: 39 of 273 awards (14%). These are the most common CAS appeals, but they are usually decided on the contract and FIFA's rules. When experts appear, they deal with valuation, foreign law or disputed documents.
Outside football, 37% of awards involve expert evidence, against 16% in football, largely because doping makes up a bigger share of the non-football cases.
Who the experts are
Across the 129 expert appearances we identified (101 different experts):
- Anti-doping science, toxicology and pharmacology: 59 appearances (46%), from laboratory scientists to pharmacokinetics specialists. See our pages on biological passport cases and contamination.
- Law: 18 (14%), most often Swiss law, but also EU, Russian, Israeli, Ecuadorian and Sierra Leonean law. See Swiss law for CAS arbitration.
- Medicine and sport science: 16 (12%), including haematologists, urologists and physicians.
- Language, behaviour and other forensic fields: 10 (8%): linguists, a lip reader, a sociologist of fan culture, a polygraph examiner and an acoustic analyst. See discrimination and fan conduct.
- Valuation, finance and transfer markets: 5 (4%). See transfer valuation.
- Forensic document examination: 4 (3%). See forensic document examination.
- The field was not clear from the award for the remaining 17.
Athletes and clubs use experts more
Where the award says who called the expert, athletes and clubs account for 64 appearances and governing bodies or anti-doping organisations for 37. Anti-doping organisations often rely on the expert panels and laboratories built into their process, while athletes have to bring their own experts to answer them.
A small pool of repeat experts
A handful of scientists appear in four or five awards each, mostly anti-doping laboratory scientists and members of the panels that review biological passport profiles, together with one Swiss law professor. For legal teams that has two consequences. The obvious experts may be conflicted, especially for an athlete facing an anti-doping organisation whose panel they sit on. And a tribunal may already know an expert's views, so independence and a fresh analysis of the specific facts matter.
What panels weigh
The awards show patterns that apply well beyond sport.
- Specific beats general. In CAS 2026/A/12149 (Pellegrini) the panel relied on an uncontradicted expert opinion that the concentration found fitted the athlete's account. General statements that something is possible carry little weight.
- Experts must stay in their field. In CAS 2024/A/10655 (WADA v JADA and Toyoda) the athlete's expert accepted that he was not an expert on the effects of the substance in question.
- Experts are often heard together. In CAS 2023/A/9960 (Sporting CP v FC Internazionale) two Swiss law professors gave evidence together and were cross-examined by both sides, and in CAS 2024/A/10374 (Wakefield) the parties' medical experts produced a joint minute.
- The panel can appoint its own expert. In CAS 2020/A/7032 (Malango v TP Mazembe) the sole arbitrator appointed an independent forensic scientist to examine a disputed signature.
What this means if you have a CAS case
- In a doping case, instruct the scientific expert before the first submission, not after: the expert's work usually decides whether the athlete can establish the source of the substance.
- In a football contract case, consider whether valuation, foreign law or a disputed document is really in issue. If so, an expert can move the outcome; if not, the cost may not be justified.
- Check conflicts early, especially with anti-doping scientists.
- Choose experts who can be heard alongside the other side's expert and still hold their ground.
For a practical guide to choosing, instructing and preparing experts for a CAS appeal, with a quick-reference table of which expert answers which issue, read our white paper Expert Evidence in Sports Arbitration.
Method and limits
The CAS publishes only some of its awards, so these figures describe the published awards on its recent decisions page, not every CAS case. We classified sport and subject from the text of each award, and counted an award as involving expert evidence where it records an expert report, opinion or testimony. Expert fields and the party that called them come from our reading of the passages that discuss each expert; where an award does not say, we have recorded it as not stated.
If you already know you need a sports expert witness, our Sports practice sets out the specialisms we cover and how to request a shortlist.