Sir Norman Bettison, the most senior serving police officer who was involved with South Yorkshire Police's discredited Hillsborough operation, said today he had “nothing to hide”.
Sir Norman, now the Chief Constable of West Yorkshire, has faced calls to quit following the publication of an independent report into the tragedy in which 96 Liverpool fans were killed.
In a statement today he insisted the behaviour of some fans in the stadium made the job of the police "harder than it needed to be".
He also defended his role in the aftermath of April 15 1989, saying: "I never altered a statement nor asked for one to be altered."
Yesterday's damning report, published by the Hillsborough Independent Panel, laid bare a shocking cover-up which attempted to shift the blame on to its 96 victims.
The panel found that 164 police statements were altered, 116 of them to remove or alter "unfavourable" comments about the policing of the match and the unfolding disaster.
They said: "The evidence shows conclusively that Liverpool fans neither caused nor contributed to the deaths of 96 men, women and children.".
The families of the football supporters killed 23 years ago said the report had vindicated them, and have pledged to carry on their fight by pursuing criminal prosecutions against those who they said should "hang their heads in shame".
Sir Norman was an off-duty South Yorkshire Police inspector when he attended the game, and was involved in an internal inquiry held by the force in its aftermath.
He said: "Fans behaviour, to the extent that it was relevant at all, made the job of the police, in the crush outside Leppings Lane turnstiles, harder than it needed to be.
"But it didn't cause the disaster any more than the sunny day that encouraged people to linger outside the stadium as kick off approached. "I held those views then, I hold them now. I have never, since hearing the Taylor evidence unfold, offered any other interpretation in public or private."
Sir Norman, who is a former chief constable of Merseyside, added: "I really welcome the disclosure of all the facts that can be known about the Hillsborough tragedy because I have absolutely nothing to hide.
"I read the 395 page report from cover to cover last night and that remains my position.
"The panel, in my view, has produced a piece of work that will stand the test of time and scrutiny.
Sir Norman said that by the time he was involved in South Yorkshire's internal inquiry, on behalf of then Deputy Chief Constable Peter Hays, West Midlands Police had taken over the formal investigation into the tragedy.
He said a second team was created by South Yorkshire Police to "work with solicitors who were representing South Yorkshire Police at the Taylor Inquiry and to vet statements from its officers that were intended to be presented to the Inquiry".
"Two South Yorkshire Police teams have been conflated in the minds of some commentators," Sir Norman added.
There was no expression of support for Sir Norman from Downing Street today when David Cameron's official spokesman was questioned by reporters on his position.
The spokesman was asked several times at a daily press briefing in Westminster whether the Prime Minister continued to have "faith" in Sir Norman as chief constable, but declined to respond directly to the question.
"The Prime Minister made a statement to the House of Commons yesterday setting out his views on this issue, the spokesman replied.
Margaret Aspinall, chairwoman of the Hillsborough Families Support Group, who lost her son James, 18, in the tragedy, said of Sir Norman Bettison's statement: "Quite frankly I am quite angry about it and I think he should resign.
"He should do the decent thing and resign, no matter what he is saying in his statement today.
"He is still saying the fans made the job more difficult for the police. He ought to be ashamed of himself. Do the decent thing Mr Bettison -resign."
London Mayor Boris Johnson earlier added his voice to the chorus of apologies made to the Hillsborough families and survivors.
Mr Johnson said he was "very, very sorry" for comments made in a 2004 Spectator article which accused people in Liverpool of failing to acknowledge the part played by drunken football fans in the disaster.
Labour called for a criminal investigation, overseen by the Independent Police Complaints Commission, into the wrongdoing uncovered by the Hillsborough report.
Shadow home secretary Yvette Cooper said the inquest into the deaths should be reopened as soon as possible and granted full access to all the original and unaltered evidence.
She added: "The double injustice for the families is in the scale and extent of the cover-up and the denial of truth by people and institutions that exist to provide just that. Clearly the inquest must focus on the terrible loss of life, and will not focus on the subsequent misinformation and altering of evidence.
"That is why we are asking the Home Office to set out a proper separate investigation into the cover-up and what happened in South Yorkshire Police, including looking at criminal charges."
Ms Cooper added: "At Hillsborough people who should have been protected were betrayed and justice was denied. The report reveals an appalling, systemic cover-up, including the alteration of over 100 statements and a campaign of misinformation.
"People need to have confidence in the police and need to be certain that they will pursue the truth in all circumstances. Even though these events took place 23 years ago, it is important to public confidence in the integrity of police forces that these issues are taken extremely seriously and investigated.
"The Chief Constable of South Yorkshire Police has rightly said that if people have broken the law then they should be prosecuted, and his force would co-operate with any new inquiry.
"We have today asked the Home Secretary to look at establishing a proper investigation into this. The most appropriate way to do this would appear to be for the Independent Police Complaints Commission to oversee a criminal investigation.
"However, I would like reassurances that the IPCC would have the powers and the investigative capacity to pursue this properly, or what alternatives there might be.
"It is clear, as the Prime Minister said yesterday, that previous inquiries have not been sufficient. Justice must be done and lessons must be learnt. Those who acted criminally or inappropriately must face the consequences and this should never be allowed to happen again."
Sir Norman's statement came as pressure was growing for criminal prosecutions to be brought against police officers involved in the disaster.
Home Affairs Committee chairman Keith Vaz has written to Home Secretary Theresa May suggesting that Tom Winsor, the new Chief Inspector of Constabulary, lead an inquiry into the role of police officers, serving and retired, into the cover up.
He also fired off letters demanding a further explanation from Sir Norman and urging South Yorkshire's Chief Constable David Crompton to launch his own criminal investigation.
Speaking this morning, Mr Crompton, who was appointed chief constable of South Yorkshire in April, said the issue of criminal responsibility for the changing of statements was the same as in any other situation.
"If someone has falsified something and it breaches the criminal law then, fair enough, that applies to anybody, whether it's in relation to Hillsborough or anything else.
"They should face prosecution, let's be clear about it," he said.
Former Cabinet minister Lord Falconer, who is advising the victims' relatives alongside Michael Mansfield QC, told BBC Breakfast: "The question of criminal proceedings needs to be looked at."
Liverpool-born shadow health secretary Andy Burnham, who was instrumental in the creation of the panel, said the role of serving police officers implicated in the report must be investigated further.
"There now has to be a process of investigation into what they did, what they knew, what they ordered, and where accountability lies," he said.
The Liverpool supporters died in a crush at Sheffield Wednesday's Hillsborough stadium on April 15 1989, where their team were to meet Nottingham Forest in an FA Cup semi-final.
The panel also concluded that potentially 41 of the 96 deaths may have been prevented had there been a "swifter, more appropriate, better focused and properly equipped response".
It is expected that the victims' relatives will meet in groups in the coming days to discuss how they take matters further.
One of their first steps will be to start the process of overturning the inquest verdicts of accidental death, which is already being considered by the Attorney General, Dominic Grieve.