A retired senior English police officer has been appointed to head a small police team set up to assist the Rosemary Nelson Inquiry.
The solicitor died after a booby-trap bomb attack on her car
Mrs Nelson died after loyalists planted a booby-trap bomb underneath her car outside her Lurgan home in March 1999.
Robert Ayling is a former acting chief constable of Kent police.
He also led the Police Complaints Authority investigation into the Metropolitan Police's handling of Stephen Lawrence's murder.
The inquiry into her murder opened at the Craigavon Civic Centre in County Armagh last month.
Retired judge Sir Michael Morland is chairing a three-strong panel examining alleged security force collusion. It will hear evidence next spring.
Sir Michael and his colleagues - ex-chief constable of South Wales Sir Anthony Burden and Dame Valerie Strachan, former chair of the board of Customs and Excise - will examine allegations that police ignored death threats against Mrs Nelson.
WHO WAS ROSEMARY NELSON?
A Catholic solicitor who came to prominence representing high profile cases
These included working for the nationalist Garvaghy Road Residents Coalition in the dispute with Orangemen over Drumcree
The 40-year-old mother-of-three was killed in a booby-trap car bomb near her home on 15 March 1999
A splinter loyalist group, the Red Hand Defenders, said it carried out the murder
Mrs Nelson's murder was carried out by the Red Hand Defenders, which is a cover name for the Ulster Defence Association and Loyalist Volunteer Force.
The government agreed to set up an inquiry into Mrs Nelson's death following the recommendations of retired Canadian Judge Peter Cory.
He was appointed by the British and Irish governments in 2001 and has delivered six reports to the London and Dublin administrations about a total of eight killings on both sides of the border.
Mrs Nelson came to public prominence as a solicitor representing Catholic residents of Portadown embroiled in the dispute over the Orange Drumcree parade.
The three-strong panel is examining collusion allegations
The mother of three had alleged that she had received death threats from members of the Royal Ulster Constabulary.
Her family says that the threats came because of her willingness to speak publicly about alleged sectarianism among the security forces and collusion with loyalist paramilitaries.
Her death came two weeks before she had been expected to meet a police watchdog about the alleged death threats.
There have been allegations of security force collusion in the killing of the 40-year-old solicitor because of her role as the legal representative for the nationalist Garvaghy Road Residents' Coalition and other high profile cases.