The allegation about the 2006 in Co Donegal was made by a man who claimed he was also a paid state agent in the IRA.
The man made a series of claims, on an anonymous basis, to BBC Northern Ireland’s Spotlight programme.
Commenting on last night’s BBC Spotlight programme TUV leader Jim Allister said: “IRA murders have so frequently punctuated the so-called peace process that many of them slip from public memory. While the Provo murders of Robert McCartney, Paul Quinn and Kevin McGuigan may have been deemed newsworthy for a few days or even a few weeks ultimately the political process carried on regardless.
“But every so often the people of Northern Ireland are reminded of the ugly truth behind the facade of the “peace process”.
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“Last night’s edition of Spotlight brought the murder of Denis Donaldson back into the headlines and reminded us of the inextricable link between Sinn Fein and the IRA.
“In light of the serious allegations made in the programme it is incumbent upon the Garda to interview Gerry Adams about the murder of Mr Donaldson.
“There is also an onus on the BBC to hand over all material which they possess relevant to the investigation. The pursuit of justice in a murder investigation should trump all other concerns.
“Less than a year ago we were reminded that the IRA Army Council continues to operate and that it is regarded as overseeing the whole Republican movement, including Sinn Fein. These latest allegations should cause all Unionists to search their consciences about the morality of maintaining Sinn Fein/IRA in government.”
Gerry Adams has rejected the BBC claims and has always denied being in the IRA.
Mr Adams’s party colleague Gerry Kelly dismissed the documentary as a “collection of discredited conspiracy theories”.