Chief Constable George Hamilton also discussed the use of the term collusion.
Chief Constable George Hamilton has said people died as a result of bad policing during the Troubles.
He made the comments at an event focused on legacy issues in Northern Ireland, addressing an audience at Queen's University.
Covering topics which ranged from the usefulness of the term 'collusion', ongoing changes to policing, and past failures in policing, Mr Hamilton said numerous recent reviews of policing issues told us "policing in the past was not always as it should have been".
"The problem was much bigger and more complex than the 'few bad apples' analogy that has been articulated previously," Mr Hamilton said.
"In the absence of any regulatory framework for managing 'agents' police officers were left to set their own standards, they were unaccountable to the law because there was no law.
"They were unaccountable to their fellow citizens. Policing was being done in a vacuum that allowed unregulated practice. Honest individuals were placed in impossible situations, having to choose between bad and worse.
"Many people lived; but some people also died as a result of that practice."
"There should be no hiding place for anyone who broke the law or acted with criminal intent – be they police officer or paramilitary," Mr Hamilton added.
"A significant difference between investigating police actions in the past and investigating paramilitaries in the past – is that the police kept records.
"They were different times and the record keeping was not to the standards that it is today, but I have ensured that the Ombudsman has unfettered access to the millions of pieces of information the Police Service holds."
Mr Hamilton, who joined the RUC in 1985, hit out at media coverage of legacy policing issues, saying the "hunt for media headlines and the necessary editing to fit programme time slots can mean that this complex issue is dealt with insensitively or indeed inaccurately".
"For some people, anything other than an outright acceptance of the assertion of collusion is immediately viewed, not only as defensive but clear evidence that I am either naive or continuing to act as part of a state cover-up for the wrongs of the past," he said.
Chief Constable Hamilton said the term 'collusion', which "has no agreed definition", is "damaging policing; not just policing in the past but policing in the present day. And if we are not careful, it will damage policing in the future".
Mr Hamilton welcomed the publication of the consultation on addressing the legacy of Northern Ireland's past, which was published at the end of last week.
In his conclusion he added: "Further progress on dealing with the past will require political leadership and financial investment. I hope that we will see both materialise in the near future.
"The politicians must take responsibility for making progress, but they cannot do it by themselves. It’s up to us - the people on this stage; the people in this room; and the many individuals and families who still hurt to this day – to help them find a way through."
In recent days focus has returned to the investigation of historical killings in Northern Ireland, with Prime Minister Theresa May earlier this month calling the current system for historical investigation "patently unfair" in the House of Commons.
Last week it was unveiled that a four-month public consultation would take place to source the public's views on a series of new mechanisms to investigate, document and uncover the truth around killings during the 30-year conflict.
Under the proposals, the HIU would deal with 1,700 deaths in just five years.
There are reported divides within the Government over the creation of a Historical Investigations Unit (HIU) - agreed under the 2014 Stormont house agreement - with resistance over the prosecution of veteran ex-soldiers.
Monday's event at Queen's was held by the Victims & Dealing with the Past project, funded by the Arts & Humanities Research Council.
Also speaking at the event were Dr Michael Maguire, Northern Ireland's Police Ombudsman, and former Director of Public Prosecutions Barra McGrory.