SAS soldiers accused of war crimes have launched a legal challenge against a High Court judge who barred them from hearings in which whistleblowers give anonymous evidence to the Independent Inquiry Relating to Afghanistan.

The soldiers say Lord Justice Haddon-Cave acted unlawfully and breached the principle of open justice by ordering that some witnesses may give testimony with only a skeleton legal team present. The inquiry is examining allegations that at least 80 unarmed Afghans were executed by members of the Special Air Service between 2010 and 2013.

Legal papers filed for the judicial review say the inquiry was approached by witnesses who would only give evidence on terms of complete anonymity and with no one else present. The filings state there is evidence relating to an occasion during a deliberate detention operation when an individual was shot in the head while he slept. According to the documents, the laws of armed conflict and the soldiers' rules of engagement required that the individual should have been arrested.

The Ministry of Defence Witness Legal Team has applied for the judicial review on behalf of the soldiers. The application argues the judge's ruling breaches the Inquiries Act 2005 and could result in evidence being untested and accepted at face value. The soldiers' lawyers asked the court to require "exacting standards of fairness" for the accused and for relatives of the deceased.

The inquiry has been sitting at the High Court in London for two years and has heard a range of allegations about conduct by UK forces in Afghanistan. The judicial review application could temporarily halt the inquiry while the court considers the legal challenge. The inquiry said it would not comment on the judicial review proceedings.

A Ministry of Defence spokesperson said Special Forces personnel had "fought with bravery around the world" and acknowledged the right of those involved to seek a judicial review. Colonel Hamish de Bretton-Gordon, a former Army commander, said in a statement that allegations of the severity under investigation should be subjected to appropriate scrutiny and that the soldiers' legal representatives were right to defend their clients' interests and to question the weight that can be given to anonymous accounts.

Whistleblowers have told the inquiry they would be at risk if identified. The judge's ruling allowing anonymous and private testimony was framed in those terms. The soldiers, some of whom could face criminal charges including murder, contend that exclusion from hearings where such witnesses give evidence prevents them from testing accounts and undermines open justice.

The legal dispute highlights tensions between protecting witnesses who fear for their safety and ensuring procedural fairness to those accused. Inquiries may use special measures, such as anonymised testimony or private sessions, where there are credible threats to a witness's safety, but such measures are subject to legal limits and judicial oversight under the Inquiries Act.

The Daily Mail has run a campaign called "Stop The SAS Betrayal" that it says exposes mistreatment of veterans in courts, and reported nearly 200,000 people have signed a petition calling for protections for veterans against allegations tied to the Troubles. The campaign and petition were cited in public debate around prosecutions and investigations involving former service members.

If the judicial review proceeds, the High Court will be asked to determine whether the judge's procedural directions were lawful and compatible with statutory requirements. The outcome could affect how the inquiry proceeds and whether anonymous, private sessions can continue in the current form. No date for a hearing on the judicial review was disclosed by the parties.