Prime Minister Harper’s most prominent decision to call a commission of inquiry came in late 2007 when he set about to create a commission to investigate Karlheinz Schreiber’s allegations about Brian Mulroney. Here’s the text of that announcement. I’ve bold-faced the parts that seem germane in regard to Richard Colvin’s new letter.

On Friday I announced that I would be appointing an independent and impartial third party to review what course of actions may be appropriate given Mr. Schreiber’s new sworn allegations. These allegations remain unproven and untested in a court of law and arose in a private lawsuit. There are, however, now issues that go beyond the private interests of the parties in the lawsuit.

Many have called for a public inquiry, including, most recently, Mr. Mulroney.

Given the conflicting information and allegations (including what appears to be some conflicting information under oath) and the extended time period over which the events referred to in various documents and allegations surrounding this matter have occurred, I have decided to ask the third party to advise the government on appropriate terms of reference for a public inquiry.

If in reviewing material, the independent party finds any prima facie evidence of criminal action he or she will identify this and advise how this should be handled and what impact, if any, it should have on the nature and timing of the inquiry.

A public inquiry is a major step and one that should only be taken when it addresses Canadians’ interest, not those of the various parties, whether Mr. Schreiber, Mr. Mulroney or political parties. That is why it is important that we engage the necessary independent expertise and take the time to ensure that the terms of reference meet that test.

This decision set a bar. If the prime minister strikes commissions of inquiry only when Brian Mulroney requests them, he should say so. If resolving Colvin’s allegations is not in the public interest, the prime minister should explain why not. If the proper response to unproven allegations is no longer to seek proof or disproof, the prime minister should tell us why that is no longer his response. If Richard Colvin, who remains a salaried and trusted public servant, is less credible than Karlheinz Schreiber, who was the subject of concerted extradition efforts by the German government at the time he made his allegations, the prime minister should explain why Colvin’s credibility is so limited, and why he continues to be entrusted with serious responsibilities on behalf of the Canadian federal state.