Commander Stephen Clayman, who is leading the national inquiry known as Operation Olympos, said the investigation team would need to nearly double in size, from 111 to 210 detectives, to meet its target of submitting files to prosecutors by late 2027 or early 2028.
He said the projected budget for the investigation was up to £19.3 million for 2026/27 and beyond. The Home Office has so far allocated £2.8m in special grant funding, leaving a shortfall of £16.5m.
Without further resources, he warned, the timeline would slip by as much as five years — an outcome he described as "unacceptable for those who have already been living with this for decades."
"Put simply, we do not have the luxury of time and must provide answers as soon as possible to those who so desperately deserve them," Clayman was quoted as saying.
The Horizon IT system, which began operating in 1999, falsely showed accounting shortfalls in Post Office branches. More than 900 sub-postmasters were prosecuted as a result, some were jailed, and thousands more lost their livelihoods. The scandal has been described as the worst miscarriage of justice in British history.
Clayman said detectives were already dealing with eight million documents, a number still growing, many of which required forensic review. "Only by doing this can we piece together exactly what happened, establish who knew what and understand the role suspects may have played," he said. So far, 13 of 53 people under investigation have been questioned under caution — seven more than six months ago.
FILE PHOTO: Sir Alan Bates, Founder, Justice for Subpostmasters Alliance, poses after being made a Knight Bachelor by the Princess Royal during an investiture ceremony at Windsor Castle, on September 25, 2024 in Windsor, England. (Photo Andrew Matthews - WPA Pool/Getty Images)
Sir Alan Bates questions government's commitment
Sir Alan Bates, whose campaign to expose the scandal inspired the ITV drama Mr Bates vs the Post Office, questioned the government's commitment to the inquiry. "It is all highly reminiscent of the Post Office trying to run the victims out of money in the courts, to stop us exposing the truth," he said. "It seems that the government is trying to reduce funding to minimise the impact and to push the truth further away."
Former sub-postmaster Seema Misra, who was jailed while pregnant in 2010 after being wrongly accused of stealing £74,000, told the BBC, "How can the government spend hundreds of millions of pounds on lawyers dragging this out but it's different for the common people to get justice? We need accountability."
By contrast, taxpayers paid one law firm alone £86m between 2000 and 2024 to represent the Post Office at the public inquiry. The Post Office is also currently paying a crisis PR company £2.4m for work running until January 2029 as it contests legal claims from victims.
A government spokesperson said the Horizon scandal was "an appalling injustice" and that the Home Office was "considering requests for further funding".
