Scotland’s head of prosecutions has apologised to those prosecuted in the Horizon scandal who were “failed” by the justice system – as she said 54 people may have been affected north of the border.

Initially, it was believed that around 100 people could have been caught in prosecutions stemming from the faulty system in Scotland, which has seen almost 1,000 subpostmasters and subpostmistresses face accusations of theft from post offices.

Giving a statement in Holyrood on Tuesday, Lord Advocate Dorothy Bain KC reiterated the timeline of events, which saw the Crown Office – Scotland’s prosecution service – halt proceedings based on the system in 2015.

Post Office van
The Horizon IT system resulted in hundreds of prosecutions across the UK (James Manning/PA)

This was despite repeated assurances from the Post Office of no issues with Horizon and was more than two years after prosecutors were first made aware.

Addressing the scandal, Ms Bain said: “I am very deeply troubled by what has occurred, and I remain acutely concerned that the Crown Office and Procurator Fiscal Service was repeatedly misled by the Post Office.

“Assurances which were just not true were repeatedly given.

“To those wrongfully convicted, I understand your anger and I apologise for the way you have been failed by trusted institutions and the criminal justice system and I stand beside you in your pursuit of justice.”

The Scottish Criminal Cases Review Commission (SCCRC) – the body which handles potential miscarriages of justice – the Lord Advocate said, wrote to 73 people in September 2020 who may have been falsely convicted, with 16 people coming forward, seven cases referred to the High Court and four overturned convictions.

The Crown Office also assessed past cases, finding that 54 may have been impacted by faulty evidence.

“I want to assure this chamber, those wrongly convicted, and the people of Scotland that I will do all I can do to prevent such an affront to justice and our system from ever happening again and to right the wrongs which have occurred,” the Lord Advocate said.

“I commit to transparency in the information which is held by the Crown Office and Procurator Fiscal Service, subject to the restrictions of the ongoing appeals and the public inquiry.”

The Post Office is also considered a reporting agency by the Crown Office in Scotland, meaning it can refer offences for prosecution.

The Lord Advocate told MSPs she had “sought urgent advice” on that status, while adding that an investigation into allegations of criminality on the part of the Post Office will need to wait until after the UK-wide public inquiry “and the full scale of their actions is understood”.

Prosecutors were first made aware of issues with the system in May 2013, but the Post Office said an external law firm had reviewed all potentially impacted cases and concluded there were no concerns about accuracy of evidence in Scotland as well as an independent report which found no issues with Horizon.

In August of that year, the Crown Office told prosecutors to “carefully consider” cases where Horizon was a factor, while the following month the Post Office agreed to seek expert advice and a further report to support Horizon’s robustness – which they “failed to deliver” on time, Ms Bain said.

But it was not until October 2015 when the Crown Office told its prosecutors to “assess all Post Office cases” with orders issued to “discontinue or take no action in cases which relied on evidence from the Horizon system to prove a crime had been committed”.

“During this period, the Post Office did not disclose to Scottish prosecutors the true extent of the Horizon problems as they are now known to be,” the Lord Advocate said.

“Scottish prosecutors received assurances that the system was robust.

“These were assurances that prosecutors, without the benefit of hindsight, were entitled to take at face value.

“They would not have known, nor indeed suspected, that the Post Office may not have been revealing the true extent of the Horizon problems.”

The Post Office has been asked for comment.

Scottish Tory justice spokesman Russell Findlay asked the Lord Advocate: “Why did the Crown not come clean as soon as they discovered the Horizon evidence was fundamentally flawed?”

He also questioned whether former law chief Frank Mulholland, who was Lord Advocate at the time, should answer questions before MSPs.

Scottish Labour leader Anas Sarwar said: “Ministers and the Crown Office knew of issues with the evidence from the Post Office over a decade ago in 2013.

“But we need to know why new prosecutions were only formally halted two years later and why no immediate action was taken to review all previous convictions as to whether they were unsafe.”