A campaigner and grandson of a woman killed during The Troubles has brought a High Court challenge against the appointment of the PSNI deputy chief constable as the new Garda Commissioner.

Ciaran MacAirt, whose grandmother Kathleen Irvine was one of 15 people killed by loyalists in the bombing of McGurk’s Bar in Belfast, brought the action in a bid to prevent Drew Harris from being appointed to the top role.

Mr Harris became the first Irish police chief appointed from outside the Republic when he was announced as the new commissioner in June.

Mr MacAirt, who is being represented by Kinnear and Co solicitors with the assistance of MacGeehin Toale Solicitors in Dublin, said Mr Harris was “not of the type or calibre” of person to hold such an office.

Ciaran MacAirt
Ciaran MacAirt, centre, at a protest in Belfast in 2011 (PA)

He said: “I have instructed my lawyers to bring a case to the High Court in order to challenge the appointment of the PSNI Deputy Chief Constable Drew Harris as the new Garda Commissioner.

“I consider it to be wildly inappropriate that the most senior British securocrat of the last 20 years should be even considered for this position, let alone hold the office.

“He and other senior officers in the PSNI have denied my family, and hundreds of others, access to truth, justice and accountability.

“Furthermore, it is an astonishing breach of Irish national security to install Britain’s most senior counter-insurgency practitioner as head of An Garda Siochana.

“He is simply not of the type or calibre of person to hold such an office.”

Fifteen people were killed when a UVF bomb exploded in the north Belfast bar in December 4, 1971.

McGurk's Bar
The scene in 1971 as rescuers look for survivors in the bar (PA)

The families of those killed in the atrocity have long campaigned for a fresh inquest.

The bombing was carried out by loyalists but at the time security forces blamed the IRA, prompting speculation the dead might have included IRA members who were carrying the device.

Relatives and campaigners discovered a large amount of new evidence not heard at the original inquest held the year after the bombing.

Solicitor Niall O’Murchu said: “It will be argued in that not only is the appointment a breach of Irish national security, but also it is a threat to human rights.

“As officer in control of the PSNI’s discredited HET (Historical Enquiries Team), this person oversaw the large-scale blocking of access to truth and justice and information, something for which he and his organisation have been heavily criticised for by the courts in Belfast.

“We will be seeking a ruling that this appointment is unlawful.”

Mr Harris is a former Royal Ulster Constabulary (RUC) officer and his officer father Alwyn was killed by an IRA bomb in 1989.

A spokesman for the Commissioner of Garda Siochana said it was not appropriate to comment on matters before the court.

The case will be heard in the High Court on Tuesday.