A US court has ruled that interviews given by former IRA member Dolours Price can be handed over to the PSNI.
The interviews are part of the Boston College Belfast Project, which began in 2001 and lasted five years, during which researchers interviewed members of paramilitary groups.
The interviewees took part on condition that the material would not be published until after they died.
Researchers argued that handing over the documents would harm the peace process and endanger the lives of people who took part in the project.
The Federal Appeal Court in Boston heard that journalist Ed Moloney and former IRA member Anthony McIntyre feared for the consequences if the material from the interviews they conducted was released.
Mr McIntyre has described the ruling as "putting lives at risk".
The Boston College project was an oral history of the Troubles from the eye-witness perspective of those most deeply involved.
The interview with Ms Price is relevant because she allegedly claimed in a separate interview that she had driven mother-of-ten Jean McConville to her death in the 1970s.
In her ruling, Chief Judge Sandra Lynch acknowledged that the researchers had some constitutional right to freedom of speech.
However, she said they could not hold a veto over the investigation of criminal activity.
Jim Cotter, one of the researchers' lawyers, said he was "tremendously disappointed" by the ruling.
Mr Cotter said: "I don't like losing a case based on the law, but in this case I'm more concerned about the safety of our clients and the participants in the Belfast Project.
"This is just going to raise old issues that were put to rest with the Good Friday Agreement."
It is understood no material will be handed over to the PSNI until a ruling is made on a second subpoena for other materials from the Boston College project.
That ruling is expected in the coming weeks and lawyers on behalf of Anthony McIntyre say that that ruling will determine whether they will apply to the High Court in Belfast to bring forward a hearing to challenge the PSNI decision to seek to continue to gain interviews given by Ms Price.
It is also understood the second subpoena relates to interviews given by 7 other former IRA members.
Jean McConville's son in law, Seamus McKendry has said the tapes must be handed over to the PSNI.