A DUP assembly member has been criticised for drawing parallels between a discredited report on Bloody Sunday and the High Court ruling on Brexit.
Christopher Stalford made his remarks on Facebook after last week's judgment that parliament must start the formal process of the UK leaving the European Union.
The South Belfast MLA wrote: "Loving the irony of those who campaigned for decades to overturn the work of law lords like Widgery suddenly declaring that judges are sacrosanct and their rulings should be accepted always. Wind yer necks in!"
Thirteen people were killed when British paratroopers opened fire on civil rights marchers in Derry city in 1972. A fourteenth died later.
The 1972 Widgery inquiry was branded a "whitewash" by campaigners as it blamed march organisers for the deaths and exonerated soldiers.
Its findings were overturned in 2010 by the Saville inquiry, which cleared the names of those who died and led to an unprecedented apology from then British prime minister David Cameron.
SDLP leader Colum Eastwood, a former member of the Bloody Sunday Trust, said Mr Stalford had "egregiously crossed a line" and urged him to withdraw the remarks.
"We're well used to duplicity from the Leave campaign but to draw any parallels between the Brexit case and the Widgery report which whitewashed the involvement of British state forces in the murder of 14 civilians on Bloody Sunday is an abominable position," the Foyle MLA said.
"There is no comparison between the long and hard struggle that the Bloody Sunday families had to endure to overturn a rank injustice and a court ruling that MPs should vote on Brexit."
But defending the comments, a DUP spokesman said: "It is entirely possible to highlight where others have criticised the outcomes reached by a judge without that inferring support for those rulings.
"Nor does highlighting the criticisms of others make any comparison between that case and any current case."
