The Alliance MP made the call in a letter to Northern Ireland Secretary of State Theresa Villiers as a DUP petition of concern vetoed an Assembly motion expressing worry about accusations made in a BBC Spotlight programme last week and seeking an investigation.
It came in addition to Alliance correspondence to the Parliamentary Standards Commissioner Sir Douglas Bain and Head of the Northern Ireland Civil Service Dr Malcolm McKibbin calling for an investigation into the episode.
Mrs Long said she has urged Ms Villiers to convene an independent inquiry after concern over both the allegations and also the “increasing abuse” of the petition of concern mechanism in the Assembly, which the DUP used to effectively block the motion, despite such a move having the support of every other party there.
“Given the seriousness of the allegations with respect to UK public funds, the corrosive effect which such allegations have on public confidence in politics and the wider public concern which they raise, I believe a truly independent inquiry is required,” she said.
“I have requested the Secretary of State uses her powers under the Public Inquiries Act (2005) to initiate one immediately and I hope that she does so as soon as possible. I have also asked her to use the Northern Ireland Miscellaneous Provisions Bill currently making its way through Westminster to address the democratic deficit created by the petition of concern mechanism and implement a weighted majority voting system, which would not allow any single party to over-ride the wishes of the Assembly as a whole.
“The petition of concern was designed to offer protection to minorities within the Assembly, where decisions of a sensitive nature risked being imposed upon them against their will. Its use in this case to protect the interest of one party in circumstances where there is widespread and cross-community support for a motion is a clear abuse of the mechanism and makes a strong case for urgent reform.”