An expanded role for British intelligence in Northern Ireland at the expense of the PSNI is a matter of concern, the Policing Oversight Commissioner has warned.
Al Hutchinson, who monitors the introduction of the Patten reforms on policing, said such a move away from the PSNI's intelligence-gathering operations amounted to "profound potential implications for the police service".
Under the plans, MI5 is to investigate paramilitary groups and their activities, while the police are to gather intelligence on "ordinary" crime.
Following publication of his 16th report, Mr Hutchinson said any such transfer should not impede the PSNI's ability to investigate organised crime in which paramilitaries are involved.
Mr Hutchinson, a former senior officer with the Royal Canadian Mounted Police, said that 124 of Patten's 175 recommendations had now been successfully completed, 10 more since his last report.
He said "tremendous progress" had been made in the five years since the PSNI was formed out of the former RUC.
However, he criticised the delay in the provision of a built-for-purpose police training college, which has been held up by a shortage of funds.
PSNI recruits are currently trained at a former catering college at Garnerville, east Belfast. A new college, with institutional links to the Garda training college, is planned for a site near Cookstown, Co Tyrone.
Some £90 million (€130.5 million) has been committed to the project, but it is claimed this is £40 million (€58 million) short of what is required.
Mr Hutchinson called on the British government to make good the shortfall so that the college could soon be built.
Policing Board chairman Sir Desmond Rea welcomed Mr Hutchinson's comments.
"While the government has made available £90 million, there remains a shortfall, without which the college, as planned, simply cannot be built."
Using some of his most direct language yet, Mr Hutchinson again urged Sinn Féin to endorse fully the new policing dispensation.
He said what was required from the party was the political commitment to do so.
"Virtually everything is on a good track to improvement. I don't know why they would hesitate in joining from a practical perspective."