On July 23, 2015, the Respondents served an affidavit sworn by Professor Christopher P. Manfredi, professor of Political Science at McGill University.

Professor Manfredi was retained on behalf of the respondents to provide an expert opinion on the following questions:

1. Whether there is a constitutional convention in relation to the timing of Prime Ministerial advice on Senate appointments and, if so, the scope of this convention.

2. Whether there is a constitutional convention that the Prime Minister must advise the Governor General to summon a person to fill a vacancy in the Senate within a fixed period of time after a vacancy occurs.

Professor Manfredi’s affidavit concludes that:

a) Prime Ministers generally take as much time as they consider necessary under the particular circumstances of each case to fill Senate vacancies;

b) Although Prime Minister fill vacancies according to their own timelines, and often allow vacancies to build up in the Senate, the evidence is that they do not allow Senate vacancies to remain unfilled indefinitely;

c) There is no evidence of a convention, based on a sample of 220 Senate vacancies, that the Prime Minister must advise the Governor General to summon a person to fill a vacancy in the Senate within a fixed period of time after a vacancy occurs;

d) Prime Ministers have broad discretion in determining the time delay in filling Senate vacancies.

A complete copy of Professor Manfredi’s affidavit is available for download (7MB, PDF).

None of the evidence produced in the application has yet been tested in Court or subjected to cross-examination. A hearing of the application on its merits has not yet been scheduled.