Suspects allegedly involved in the Kingsmill massacre should be named during an inquest in Northern Ireland, a lawyer for relatives has said.
A coroner in England is to appeal against a ruling to identify suspects in the IRA's Birmingham pub bombings during inquests.
Lawyers involved in the Kingsmill inquest into the shooting of 10 Protestant workmen by republicans in January 1976 said the matter would probably go to the UK's highest court, with implications for Northern Ireland.
Alan Kane QC, for the families, said: "Suspects in this case ought not to have the benefit of hiding behind ciphers but rather their identities should be made public."
The Kingsmill inquest was told the issue around naming the Birmingham suspects was likely to end up in the UK Supreme Court.
Final settlement of the matter could be some time away.
Barrister for the security forces Peter Coll QC said: "The issue is about removing ciphers.
"There is a risk that in waiting for Birmingham that does not speak to that issue but a more fundamental issue.
"If they consider that it is not open to consider individualisation, where does that leave us, because we have been looking at this?"
More legal discussions are to take place on issues surrounding suspects.
The role of the On The Runs scheme and its impact on Kingsmill is expected to be discussed during a further preliminary hearing in March.
Kingsmill was a sectarian atrocity by republican terrorists who ordered a group of Protestant textile workers off a bus, lined them up and shot them on a roadside in South Armagh.
Ten men died. Alan Black suffered 18 gunshot wounds and survived.
His 19-year-old apprentice in the factory, Robert Chambers, fell across his legs as the shooting took place. The teenager was calling for his mother as he was shot in the face.
Former Sinn Fein MP for West Tyrone Barry McElduff resigned last month after he was criticised for tweeting a video with a loaf of Kingsmill bread on his head on the anniversary of the killings.