A BBC Panorama programme claimed the killings of civilians in Afghanistan and Iraq have been covered up by the state.
Leaked documents allegedly contain evidence implicating British troops in killing children and torturing civilians.
The ICC said it has taken the accusations “very seriously”, according to the BBC. “The ICC said it would independently assess the BBC’s findings and would begin a landmark case if it believed the government was shielding soldiers from prosecution,” the corporation reported on Monday morning.
Balkees Jarrah, senior counsel at Human Rights Watch, told The Independent: “Over the years, information has emerged indicating widespread, serious abuses of Iraqis in British detention, including assaults, torture and deaths. At the end of the day, the war crimes allegations stemming from the UK’s involvement in Iraq will not go away unless the British justice system shows itself capable of meaningfully addressing them to the highest level.”
Ms Jarrah added: “The ICC prosecutor has already determined there is a basis to believe that members of the UK armed forces committed war crimes against people in their custody in Iraq.
“She will no doubt be taking a very close look at the BBC’s report about a possible cover-up in deciding whether or not to formally step in.”
The Ministry of Defence (MoD) has said the allegations are unsubstantiated.
The year-long BBC and Sunday Times investigation said it had obtained new evidence from the Iraq Historic Allegations Team (Ihat), which investigated alleged war crimes committed by British soldiers in Iraq, and Operation Northmoor, which looked into alleged war crimes in Afghanistan.
The government closed Ihat and Operation Northmoor in 2017 after Phil Shiner, a solicitor who had taken more than 1,000 cases to Ihat, was struck off from practising law amid allegations he had paid people in Iraq to find clients.
But some former Ihat and Operation Northmoor investigators said Mr Shiner’s actions were used as an excuse to close down the inquiries.
No case investigated by Ihat or Operation Northmoor has led to a prosecution.
The ICC has previously concluded it was credible that British troops committed war crimes in Iraq related to the mistreatment of detainees.
The investigation, which will be shown on BBC1 at 9pm on Monday night, claims to have found evidence of murders by an SAS soldier, as well as deaths in custody, beatings, torture and sexual abuse of detainees by members of the Black Watch.
A senior SAS commander was referred to prosecutors for attempting to pervert the course of justice, the investigation claims.
Rachel Logan, Amnesty International UK’s legal programme director, said: “Reports of killings and torture by British troops in Afghanistan and Iraq, and a subsequent cover up, are deeply troubling.
“If true, those responsible for sanctioning and carrying out torture and other war crimes, at all levels, must be held accountable and where appropriate, prosecuted.
“Instead of consistently seeking to sweep these most serious of allegations under the carpet, Britain needs to stand up against torture, uphold its international commitments and show it treats these cases with the seriousness they deserve.”
Responding to the allegations, an MoD spokesperson told The Independent: “Allegations that the MoD interfered with investigations or prosecution decisions relating to the conduct of UK forces in Iraq and Afghanistan are untrue.
“Throughout the process the decisions of prosecutors and the investigators have been independent of the MoD and involved external oversight and legal advice.”
Commenting after reports the ICC could investigate the British military, a spokesperson for Boris Johnson, the prime minister, said: ”Allegations that have been made that the MoD interfered in investigations of the prosecutions are untrue.
“The service police carried out an extensive investigation into allegations about the conduct of forces in both Iraq and Afghanistan. The independent Service Prosecuting Authority decided not to prosecute any of the cases referred to it.”
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