The UK's veterans' minister reportedly opposed the 2019 decision to shut down an investigation into war crimes by special forces in Afghanistan.
Among those giving evidence at the hearings in London was Mansour Aziz, who said his brother and sister-in-law were shot dead in an SAS raid on their home on August 6, 2012, as they slept. Two of their children were also shot and injured.
"We are asking for the court to listen to these children and bring justice," Aziz said in statement via his British legal representatives Leigh Day, stressing that the family want "to know the truth."
An email from an SAS sergeant-major that came to light during a judicial review described their killings as only "the latest massacre" — suggesting that there had been others.
British mainstream media said it had learned that Veteran's Affairs Minister Johnny Mercer wrote to then-Defense Secretary Ben Wallace in 2019 objecting to the closure of the Operation Northmoor probe.
The investigation was opened in 2014 to examine a total of 675 accusations against British forces in Afghanistan.
Mercer, who served as an army officer in the conflict and worked with SAS troopers, raised concerns that they may have murdered unarmed Afghan citizens and then planted weapons by their bodies to justify the killings.
Despite Mercer's intervention, the Northmoor investigation was closed in late 2019. But in 2022 the government ordered the new inquiry by Lord Justice Haddon-Cave after the state broadcaster's Panorama news feature program detailed allegations that one SAS squadron killed 54 Afghans in questionable circumstances.
Mercer has held his current job three times since July 2019.
He quit in April 2021 — ironically in protest at the Overseas Operations Act, a law which protects service personnel from prosecution for actions in wars abroad, because it did not extend that cover to alleged crimes committed in the decades-long deployment in Northern Ireland.
Mercer was re-appointed by Prime Minister Boris Johnson in July 2022 after much of his cabinet resigned in a bid to force his resignation, but was sacked in the September reshuffle by Johnson's replacement Liz Truss — prompting his wife to publicly call the short-lived Tory leader an "imbecile". Mercer was re-appointed the next month by current PM Rishi Sunak.