Twenty-three individuals and organisations could face criminal charges over the Hillsborough disaster.
Ninety-six people died in the crush at the FA Cup semi-final in Sheffield between Liverpool FC and Nottingham Forest. New inquests which concluded last year found the victims were unlawfully killed and fans were not to blame.
Today Operation Resolve - the criminal investigation into the disaster - and the Independent Police Complaints Commission, or IPCC, said it had passed files on 23 suspects to the Crown Prosecution Service, or CPS.
A statement from both investigations said 15 of the suspects related to the probe into the causes of the disaster, while eight related to the IPCC inquiry into the alleged police cover-up.
Among those under criminal investigation are South Yorkshire Police, Sheffield Wednesday, Sheffield Council, Yorkshire Ambulance Service and the Football Association.
High-ranking officers at South Yorkshire Police are also under scrutiny, but not all individual suspects are police officers.
Match commander David Duckenfield is among those potentially facing criminal charges after the inquests jury ruled the 96 supporters who died were ‘unlawfully killed’ - a verdict they could only reach if they were sure his breach of duty of care to the fans had caused the deaths and amounted to ‘gross negligence’.
The Operation Resolve investigation, looking at the preparation for the match and events of the day, considered offences including gross negligence manslaughter, perverting the course of justice, misconduct in public office and offences under the Safety of Sports Ground Act 1975 and Health and Safety at Work legislation.
The IPCC probe examined both South Yorkshire Police and West Midlands Police - the force which investigated the disaster in 1989.
Investigators for the watchdog considered offences including perverting the course of justice, conspiracy to pervert the course of justice and misconduct in public office.
More than 170 allegations of police misconduct continue to be investigated by both teams.
The IPCC has found that 289 officers’ accounts were amended in the aftermath of the disaster - up from, but including, the 194 found by the Hillsborough Independent Panel in 2012.
Head of CPS special crime and counter terrorism division Sue Hemming said: "Having received files from both Hillsborough investigations, we will now assess these in order to determine whether we have sufficient material on which to make charging decisions. Charging decisions will be based on the tests set out in the Code for Crown Prosecutors."
Assistant commissioner Robert Beckley, officer in overall command of Operation Resolve, said: "Our task has been to investigate whether any individual or organisation is criminally culpable for their role either in the planning and preparation for the match or on the day of the game itself.
"The extensive file we have submitted, which contains over 35 million words, reflects four years of intense work from my teams."
IPCC deputy chair Rachel Cerfontyne said: "These criminal investigations into the circumstances surrounding the Hillsborough disaster are the largest investigations into alleged police wrongdoing ever undertaken in England and Wales.
"Conducting an inquiry of this scale and complexity, while supporting the longest running inquests in British legal history, has been a significant undertaking for the IPCC. Our criminal investigation has now substantially concluded."
Lawyer Elkan Abrahamson, director of Broudie Jackson Canter, which represents 20 of the Hillsborough families, said: "Our clients are relieved that files have finally gone to the CPS to consider criminal proceedings against 23 individuals and organisations.
"Given that the CPS have been working in tandem with the police and the IPCC for many years we believe decisions should now be taken without further delay.
"We will continue to scrutinise the process and any decisions."
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