RGP Senior Investigating Officer John McVea is to get the top job at the Gibraltar Defence Police, GBC understands.
Mr McVea arrived in Gibraltar to investigate criminal matters related to the McGrail Inquiry.
Sources say three candidates from the UK were interviewed by the Commander British Forces for the role of Chief of Police.
Mr McVea was said to have been the preferred candidate to take over from Rob Allen who has recently retired.
John McVea is a former Chief Superintendent with the Northern Ireland Police Service who, having retired, accepted a call for Mutual Aid by the RGP to investigate the McGrail Inquiry Data Breach late in 2022.
His career spanned 30-years, throughout the peace process. Of those, he spent 15 years in the serious crime branch.
Mr McVea was sworn in as a Royal Gibraltar Police officer with full constabulary powers and took on the role of Senior Investigating Officer. He led a team of RGP officers, which included officers from Dyfed Powys Police and the Police Service of Northern Ireland.
Mr McVea was paid at a rate of £500 for each day worked.
Arrests soon followed in relation to the data breach, followed by the shock arrests of the former police commissioner Ian McGrail. He was later cleared of all charges.
As the Inquiry neared, there were more arrests of former police officers who had made Whistleblower statements against Ian McGrail and senior members of the Royal Gibraltar Police. The McGrail Inquiry learned that they had received letters of guarantees signed by the Chief Minister.
Three have since been charged with attempting to pervert the course of Justice.
A senior government employee was arrested at the end of last year.
Speaking on a recent Viewpoint programme, Police Commissioner Richard Ullger said the investigations remained ongoing, although the allegations made against senior members of the RGP had been dismissed by Mr McVea.
In answer to GBC questions, an MOD Spokesperson said: “The Gibraltar Defence Police are in the process of appointing a new Chief of Police. When the usual pre-employment checks have been completed, British Forces Gibraltar will then be in a position to formally announce the official appointment of the new GDP Chief of Police.”
Meanwhile, the RGP has declined to comment.