Sinn Fein has said the family of a woman abducted and murdered by the IRA in 1972 should feel free to co-operate with police in the pursuit of justice.
MP for Newry and Armagh Conor Murphy said he was “surprised” that Michael McConville felt he could not provide information to investigators looking into his mother’s death for fear of possible reprisals.
Party president Gerry Adams is being questioned by detectives investigating the death of Belfast mother-of-10 Jean McConville.
Mr Murphy told the BBC’s Today programme: “Many people have brought information forward in relation to inquiries and we have said quite clearly over the years that if families wish to co-operate with the historical investigations team - flawed as its approach clearly and officially was found to be - then people should be free to do so.
“Many, many families have co-operated with those investigations and I’ve yet to hear of one who have suffered any intimidation as a consequence of doing that.”
He added: “I certainly feel that the McConville family are entitled to pursue justice in this case. They are entitled to pursue whatever avenue they feel (appropriate) in the case of their mother, and I would certainly strongly urge that no-one interferes in that process at all.
“In cases before where this has happened, no-one has interfered - that I am aware of - in any of these processes.”
Mr McConville has said that he was still not prepared to name those involved even though he knew who they were, because of the consequences for his family.
He claimed he was too scared to tell detectives who he believed was responsible in case he or other family members were shot by republican extremists for informing.
However his sister said she is prepared to name the people responsible for her mother’s death.