The Department of the Taoiseach has released letters from Alan Shatter - where the former minister tries to exclude himself from an investigation into alleged Garda malpractice.

Alan Shatter's lawyers argued that it would be "gravely unconstitutional" for a Commission of Inquiry to investigate Alan Shatter's performance in office, when he is separately taking legal action against the Guerin report.

Shatter's lawyers went on to say Shatter expressed grave concerns that the commission of investigation into the Guerin Report would interfere with his High Court challenge to the same.

The letters published by Enda Kenny this evening show the lengths to which Alan Shatter and his legal team went to try and stop a Commission of Inquiry from investigating his performance as Minister for Justice.

Brian Gallagher - a partner in Alan Shatter's own legal firm - said that the Commission of Investigation could not be separated from the findings of the Guerin Report, which reached wrong and "unconstitutional" conclusions.

The Department of the Taoiseach dismissed his concerns - saying the alleged Garda malpractice investigated by Guerin was important enough to merit a full Commission of Investigation.

Deputy Shatter himself then wrote to the Ceann Comhairle - demanding that the terms of reference be changed, saying they would otherwise be a "direct interference" in his High Court case against Guerin.

The Ceann Comhairle could not change those terms of reference - but did agree that no debate could be allowed, a decision that led to last week's walkout in the Dáil.