decisions

World Athletics v Mr Hillary Kipchirchir Chepkwony

  • Sport: Athletics
  • Issue: Arbitration
  • Type: Anti-Doping
  • Tribunal: Charles Hollander KC (Chair), Julien Berenger , Dr Thomas Murray
  • Decision date: 01 May 2026
  • Outcome: 4-year ineligibility

A decision in the case of World Athletics (WA) against Mr Hillary Kipchirchir Chepkwony has been issued by the Disciplinary and Appeals Tribunal (DAT).

Mr Chepkwony is a 27-year-old long-distance runner from Kenya and is an International-Level Athlete for the purposes of the World Athletics Anti-Doping Rules (ADR).

On 8 December 2025, the Athletics Integrity Unit (AIU) issued Mr Chepkwony with a Notice of Charge for the Use of a Prohibited Substance or Prohibited Method pursuant to Rule 2.2 ADR.

The Charge arose from abnormalities identified in Mr Chepkwony’s Athlete Biological Passport (ABP). Between 20 September 2022 and 2 January 2025, 17 blood samples were collected from Mr Chepkwony and analysed by World Anti-Doping Agency (WADA) accredited laboratories. The Joint Expert Panel (JEP) identified abnormalities in “Sample 14” and “Sample 15”, collected on 24 August 2024 and 29 August 2024, respectively. The JEP unanimously concluded that it was “highly likely” that the abnormalities were the result of the Use of a Prohibited Substance or Prohibited Method (blood doping) and “unlikely” to be the result of any other cause. Consequently, the Athlete Passport Management Unit (APMU) declared an Adverse Passport Finding (APF) against Mr Chepkwony.

Following notification of the APF, Mr Chepkwony provided an explanation for the abnormalities. In a Second Joint Opinion dated 24 October 2025, the JEP unanimously maintained its opinion that it was “highly likely” that the abnormal haematological pattern observed in Samples 14 and 15 resulted from the Use of a Prohibited Substance or Prohibited Method and “highly unlikely” that it resulted from a normal physiological or pathological condition.

Mr Chepkwony denied the Charge and requested a hearing before the DAT. Mr Charles Hollander KC was appointed to sit as Chair of the Panel on 5 January 2026, with Mr Julien Berenger and Dr Thomas Murray appointed as Panel members on 13 April 2026 and 14 April 2026, respectively.

Mr Chepkwony did not seek to explain the abnormalities by reference to any underlying medical condition, although it was asserted that he had been unwell at the relevant time. Instead, Mr Chepkwony argued that Samples 14 and 15 were inadmissible because of alleged deficiencies in the transport, storage and Testing process which rendered them unreliable. In relation to Sample 15, Mr Chepkwony also relied upon the results of a private blood test conducted on the same day.

The Panel heard oral evidence from the three members of the JEP and from Professor Jean-Claude Alvarez, who gave expert evidence on behalf of Mr Chepkwony.

The Panel found the evidence of the JEP to be reliable and helpful and gave it greater weight than the evidence of Professor Alvarez. The Panel expressed serious concerns regarding Professor Alvarez’s evidence, finding that a number of his assertions were unsupported, inconsistent with the applicable WADA standards and, in certain respects, materially misstated previous CAS jurisprudence.

In relation to Sample 14, the Panel rejected Mr Chepkwony’s argument that the transport and storage conditions invalidated the Sample and accepted the JEP’s evidence that the Blood Stability Score (BSS) was within acceptable parameters and that there had been no breach of the International Standard for Testing and Investigations (ISTI).

In relation to Sample 15, the Panel rejected Mr Chepkwony’s challenges concerning laboratory quality assessment issues and the reliance placed upon a private blood test. The Panel noted that the private sample had not been analysed by a WADA-accredited laboratory and did not measure RET%, which was the key abnormal parameter in Sample 15.

The JEP’s evidence was that the low RET% values observed in Samples 14 and 15 were consistent with the “aftercycle” of a course of doping, more likely involving erythropoietin (EPO) than a blood transfusion.

The Panel concluded that WA had established an Anti-Doping Rule Violation pursuant to Rule 2.2 ADR to the requisite standard of comfortable satisfaction. In reaching its decision on sanction, the Panel, however, noted concerns regarding the fairness of the timing of the proceedings and observed that, although Mr Chepkwony had voluntarily refrained from competing from July 2025 onwards, the ADR did not permit the sanction to be backdated in the circumstances of the case.

Accordingly, a period of Ineligibility of four (4) years was imposed pursuant to Rules 10.1, 10.2, 10.10 and 10.11 ADR. The sanction will run until 7 December 2029. In addition, all competitive results obtained by Mr Chepkwony from 24 August 2024 onwards are Disqualified, including the forfeiture of any medals, titles, points, prize money and prizes.

Sport Resolutions is the independent Secretariat to the World Athletics Disciplinary and Appeals Tribunal.

A copy of the full decision can be accessed via the related links tab on the right-hand side.

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