Northern Ireland’s new police chief constable is expected to be named later.

George Hamilton steps down as head of the Police Service of Northern Ireland (PSNI) next month.

Four candidates to replace him in the £207,500-a-year job include officers from within the force and the rest of the UK.

They are: PSNI deputy chief constable Stephen Martin; assistant chief constable Mark Hamilton; Bedfordshire chief constable Jon Boutcher, who is probing the activities of the Army’s highest ranking spy during the Troubles; and former chief constable of Cheshire Police Simon Byrne.

Interviews were carried out on Thursday and more are due on Friday before independent oversight body the Policing Board meets to agree its choice.

The next chief is being chosen by a panel of seven board members.

Dolores Kelly comments
Dolores Kelly of the SDLP (Liam McBurney/PA)

Four of the main five Stormont political parties are represented but the nationalist SDLP’s Dolores Kelly withdrew for personal reasons.

An announcement is due on Friday evening after Northern Ireland Secretary Karen Bradley approves the appointment in the absence of a justice minister at Stormont.

Independent recruitment specialists have been hired to oversee the process.

A senior occupational psychologist will “dip sample” notes taken by selection panel members and ask them to justify the marks they allocate to shortlisted candidates.

A preference for applicants to have served outside Northern Ireland has been dropped from the list of desirable criteria in the selection process.

European Parliament election
Sinn Fein leader Mary Lou McDonald (Michelle Devane/PA)

The steps are among several beefed-up scrutiny measures introduced following controversial comments by Sinn Fein leader Mary Lou McDonald on who should succeed Mr Hamilton.

Mrs McDonald was accused of undermining the integrity of the recruitment exercise when she said she did not have confidence in any prospective candidate from within the PSNI.

Her remarks in February prompted calls for the customary Sinn Fein representative to be excluded from the selection panel.

Those demands were ultimately resisted, with board members instead agreeing to introduce new quality assurance measures to safeguard the process.

Mr Boutcher is leading an operation probing the activities of a high-ranking Army mole within the IRA who was known as Stakeknife during the Troubles.