One of Northern Ireland's most senior police officers has warned it will take "a lifetime" to resolve Troubles-related killings.
Deputy Chief Constable Drew Harris said resources should be focused on reconciliation rather than in the current process for dealing with legacy cases, which is heavily police-reliant.
The PSNI's Legacy Support Unit - the body responsible for all aspects of disclosure of material to HM Coroner in legacy inquests - is swamped under the work of preparing "millions" of pages of documents.
Currently 53 cases, relating to 86 deaths dating back to the early 1970s, are listed for inquest. That figure could potentially rise over the next few years.
Some of the most notorious inquests to be dealt with include the UVF murder of 76-year-old Roseanne Mallon, the Ballymurphy shootings and the Kingsmill massacre.
Mr Harris warned that dealing with these inquests involves "decades of work". On top of that the PSNI's Legacy Investigations Branch has almost 1,000 cases to examine or review.
Mr Harris said: "We've entered into these processes, not just as police but as a society, probably without a thought of what the end game is. This is literally decades of work that we have embarked upon in respect of coronal inquests.
"Then there is also the review work we have to compete. That is at least a decade of work. And time is moving on. Some of these events are now 40 years old and that has an impact as well."
The Stormont House Agreement (SHA) proposes to address the legacy of the Troubles with the creation of a number of new agencies, including a Historical Investigations Unit to examine unsolved murders.
However, until the SHA is implemented, dealing with the toxic past remains with the PSNI.
Mr Harris said: "There is not in effect a solution with the police service about our past. We can play our part, we want to play our part, we want to play both our moral and legal responsibilities, but there is now a wider societal and political issue about how we actually deal with the past.
"If we have resources they should be focused on reconciliation, rather than resources that have to go into this.
"Our documents (for coroner's inquests) run to millions of pages. Going forward it is not possible in a lifetime to get through this.
"We are following through, and we respect the coroner's process, but as a society I'm not sure how much further it will take us."
Mr Harris also warned of the implications for policing should the SHA not be implemented.
He said there would be "an immediate draw on our ability to deliver against today's policing plan and our ability to keep people safe in the here and now."
Currently 70 officers are dedicated to legacy probes. Mr Harris said these experienced officers could otherwise be dealing with "matters of serious harm".