Chief Constable Hugh Orde has said a change in the law might be necessary to keep paramilitary chiefs off the streets.
Hugh Orde put pressure on paramilitary chiefs
On his first anniversary in charge of Northern Ireland's police service, Mr Orde said on Friday that although he had been successful in clamping down on loyalist paramilitary groups, he was concerned at how quickly some of the key players had been released.
"One of my frustrations over the year is where we have been successful in taking out what we would describe as major players, some of whom are now serving long-term imprisonment," he said.
"It was the speed with which they managed to get bail when charged with very serious criminal offences."
"It may be we need a change in legislation."
Although the Ulster Defence Association, Northern Ireland's biggest loyalist paramilitary organisation, has called a 12-month end to all military operations, the chief constable sceptical about its motives.
However, he stressed that there was no intelligence warning that the Provisional IRA's ceasefire was about to break down.
But the chief constable said mainstream republicans still had more to do in order to help drag the Northern Ireland peace process out of crisis.
Mr Orde said: "There are a number of cases going through the court process at the minute suggesting other activity continues.
"At some stage they (the IRA) have got to make a decision and that's really what normalisation is all about.
"The big disappointment of the last year is that
we didn't move the political debate and the political agenda didn't move on as quickly as policing has moved on."
One of the major threats to peace still came from dissident republican
groupings such as the Real IRA and Continuity IRA, he confirmed.
Mr Orde said he could not rule out the possibility of a republican feud.
Conference on corruption
Meanwhile, police chief Sir John Stevens, who uncovered collusion between paramilitary killers and the security forces, is to attend a Northern Ireland conference on corruption.
The Metropolitan Commissioner is one of more than 200 delegates, including chief constables and heads of complaints from around the world, who have been invited to the November conference on corruption within the ranks.
Police officers from South Africa, Australian, Hong Kong and Canada will discuss police use of force.
The meeting is being organised by Northern Ireland Police Ombudsman Nuala O'Loan.
Sir John has spent 14 years investigating allegations of collusion between the security forces and loyalist paramilitaries.
He revealed that rogue elements within the police and army in Northern Ireland helped loyalist paramilitaries to murder Catholics in the late 1980s.
His report, delivered earlier this year, also found that military intelligence in Northern Ireland helped to prolong the Troubles.
The Stevens Three report found that informants and agents "were allowed to operate without effective control and to participate in terrorist crimes".