The Independent Police Complaints Commission's exposition of vast potential misconduct at and after Hillsborough by two police forces, including serious possible criminal offences, is remarkable, even dizzying, in its reach and implications. The families who lost 96 loved ones in that FA Cup semi-final at Hillsborough on 15 April 1989 will still harbour reservations; as the IPCC's report itself acknowledges, the justice process has serially let them down in the 23 years since.

But the IPCC's statement setting out all those let-downs will give them hope that the authorities are now serious about righting the multiple wrongs of Hillsborough. The director of public prosecutions, Keir Starmer QC, confirmed that the Crown Prosecution Service will investigate "whether there is now sufficient evidence to charge any individual or corporate body with any criminal offence".

The IPCC's deputy chair, Deborah Glass, explained the scope of the investigation and the range of possible offences. What happened at Hillsborough on the day, causing 96 people to die while many police officers stood around and ambulances waited outside, will be examined again. Manslaughter "through gross negligence" by the South Yorkshire police, including the failure to activate the emergency rescue plan, is a possibility.

Then South Yorkshire police's hideous campaign, now exposed in excruciating detail, to avoid blame for the deaths and seek to shift it on to the traumatised supporters themselves, may amount to perverting the course of justice.

The IPCC and DPP will also examine the adequacy of the investigation carried out by the West Midlands police, which the families have always resented as inadequate, probably biased, and characterised by inter-force cosiness. The families, and many survivors who were interviewed, loathed the thrust and personal approach of the West Midlands police investigation; after all these years, Glass said, there are "questions about [its] adequacy and thoroughness".

Within that, there is a new and cruel detail, about the way in which Chief Superintendent David Duckenfield, the officer in calamitous command at Hillsborough, was able to retire before he faced disciplinary proceedings. In part, the IPCC revealed, this was due to the West Midlands force's failure to take appropriate statements, under caution, from witnesses they interviewed.

The IPCC also identifies "suggestions of bias" in the investigation by Chief Constable Leslie Sharp, of Cumbria police, who exonerated South Yorkshire police's chief constable, Peter Wright, and afterwards wrote to "praise him".

Sir Norman Bettison, named in parliament in 1998 as part of South Yorkshire police's "black propaganda unit" after Hillsborough by the Merseyside MP Maria Eagle, but who rode it all out and even became Merseyside police's chief constable, faces a detailed investigation. Bettison was a member of the "Wain Group" which, the panel found, produced a report largely blaming drunk fans for the disaster.

Bettison also made efforts to influence opinion, including that of MPs, after the Taylor report principally blamed the police for the disaster. It emerged that Sir Norman, who exonerated himself the day after the panel reported, also faces a complaint that he sought to influence his own West Yorkshire police authority before it referred his alleged misconduct to the IPCC.

The families want justice now, and they will not be satisfied until people and organisations are held accountable. Yet whatever happens, this is another day of complete vindication for the their complaints, their outrage at perceived injustice, the knowledge they were subjected to police blame-shifting and cover-up, when also dealing with the needless, horrific deaths of their loved ones.

For 23 years their complaints were maddeningly dismissed, but have now been repeated back to them by the IPCC and recognised as extremely grave issues.

This vindication comes exactly one month since the last landmark one, the publication of the Hillsborough Independent Panel's 395-page report, based on 450,000 documents held by South Yorkshire police and other bodies which finally, unanswerably, established the truth.

After 23 years in which their campaign for justice was largely unheard, even scorned, by the country, the Hillsborough families are now promised the biggest ever inquiry into police misconduct. It must be faintly surreal, amid the other swirling emotions, for the families to read admiration from the the official police investigatory body, the IPCC, for "the tenacity of the Hillsborough families' long campaign for truth and justice".

Now they hope the investigations will, as promised, be swift and that they will not have to wait too much longer.