Chief Constable Sir Hugh Orde was at the centre of a deepening row with nationalist politicians in Northern Ireland tonight.
SDLP claims that they ensured his appointment to the job over four years ago provoked a ferocious backlash.
The Northern Ireland Policing Board has written a letter of protest to the SDLP's leader Mark Durkan about the appointment claims.
"The Northern Ireland Policing Board undertook a thorough, professional and legislatively compliant appointment process which was based on appointing a new chief constable solely on merit and included independent assessments," a spokeswoman said.
"The chairman of the Board (Professor Sir Desmond Rea) has written to the leader of the SDLP in relation to the comments published in an advert."
Mr Durkan used that commercial to claim the kudos for keeping out what he called the old Royal Ulster Constabulary order.
Sir Hugh won the recruitment competition over senior RUC candidates Alan McQuillan, a former senior officer in the Belfast district, now head of the Assets Recovery Agency, and fellow assistant chief constable Chris Albiston, who are now reportedly considering legal action.
The Chief Constable was a deputy assistant commissioner of the Metropolitan Police at the time of his 2002 promotion. The senior officer is due back from a trip to New York to face a stormy Policing Board meeting about the affair.
Ian Paisley's Democratic Unionist Party has called for an investigation into the SDLP's claims. DUP Board member Willie Hay said there needed to be a close look at procedures linked to Sir Hugh's appointment.
"We need to look at the scrutiny mechanism used by the members on that panel when the appointment was made to see if there are any inaccuracies," he said.
"It does call into question the members of the SDLP who sit on the Board, they need to look at their position because we all have a duty on the Board to act impartially in all aspects of policing, especially senior appointments."
He added that confidence in the Board had been shaken by recent revelations and added that an inquiry into the matter should also look at the actions of independent non-political panel members.
"It has angered a number of senior police officers in the service and a number on the ground, there is a feeling that they are being used as a political football in all of this," he added.