The Herald reported yesterday that Scottish Liberal Democrat leader Willie Rennie had renewed his call for an inquiry into the Megrahi conviction.
Now Christine Grahame has written to the Deputy PM pressing for that to be a full UK public inquiry.
Citing factors such as British Government and CIA involvement in the investigation, she states: "Under the Inquiries Act 2005 (Section 28) any inquiry undertaken by the Scottish Ministers must deal only with matters wholly within their devolved competence.
"This would restrict it to such a degree, in my view, that it would not be satisfactory, given there are political and international issues which remain unresolved."
Last August, Mr Clegg criticised the release of Abdelbaset al Megrahi two years previously on compassionate grounds as he fought cancer, although he lived on in Tripoli for 21 months.
Ms Grahame, who is a member of the Justice for Megrahi campaign, wrote to Mr Clegg: "It seems that you harbour no doubts over this conviction, but that does not chime with the sentiments, as I read them, of Willie Rennie.
"It may be that your views have shifted with the passage of time and more revelations which cast the conviction as questionable.
"You, as Deputy Prime Minister, have it within your power to deliver that public inquiry and if you do, the Scottish Government has it on record that it would support any such inquiry."