Relatives suing over the shootings in Loughgall, Co Armagh 27 years ago were granted High Court permission to add the Chief Constable as a second defendant in the lawsuit.The decision could have major significance for other so-called legacy cases, according to one of the lawyers involved. Proceedings were first issued against the MoD over the ambush which inflicted the IRA's largest loss of life during the conflict.Undercover soldiers killed eight members of the Provisionals' East Tyrone unit in May 1987 as they approached Loughgall RUC station with a bomb in a hijacked digger.The IRA men shot were Jim Lynagh, Padraig McKearney, Gerard O'Callaghan, Tony Gormley, Eugene Kelly, Patrick Kelly, Seamus Donnelly and Declan Arthurs.A civilian, Anthony Hughes, was also killed and his brother badly wounded when they were caught up in the gunfire. Lawyers representing the families of some of the IRA men who died claim the killings were unlawful.With the RUC's Mobile Support Unit also believed to have played a role in the operation, they returned to court in a bid to have the force's successor joined to the action.An application was brought in the name of Declan Arthurs' father Patrick. It was argued that a report into the ambush referred to it as an SAS/RUC operation throughout.On that basis Master Bell ordered that the Chief Constable of the PSNI, as successor in title to the Chief Constable of the RUC, be added as a defendant in the action.Outside the court Mr Arthurs' solicitor, Kevin Winters, stressed the potential implications of the ruling.He said: "This is important not just for the Loughgall families in their long-running campaign for justice, but on a wider front it's very significant for legacy litigation generally."It confirms that, despite the lengthy passage of time, if the state has material or information which has never previously been disclosed it still allows individuals to take cases even though that information isn't made known for many years."Mr Winters added: "We will now amend the pleadings to join the police in this action. The full hearing will not take place until later this year."