On Friday, Prime Minister Harper started playing Russian roulette with one of the founding institutions of the Canadian Constitutional order, the Senate.

He promised not to recommend to the Governor General any more Senate appointments daring the provinces to either agree to reforming the Senate or in the absence of such agreement to have it die by attrition as he would not appoint any more even if he was re-elected in October.

This is not only playing a dangerous game with an institution that was a key part of the Canadian Confederation bargain, its establishment a key reason why Quebec and the Atlantic provinces agreed to unite with Ontario, but Harper is yet again on a collision course with the Supreme Court on the constitutionality of his "death by attrition" strategy.

It was only in 2014 that the Court warned Harper that he could not do indirectly what he was constitutionally barred from doing directly.

He wanted to have consultative elections for Senators run by the provinces with the PM still doing the recommending to the Governor General and he wanted to shorten the term of each appointment.

The Court told him that can be done with the consent of seven provinces representing 50% of the population and it would require unanimity if he wanted to abolish it.

Consent of the provinces can't be overridden by other devious means.

Now Harper is trying to force that consent or willing to have the Senate abolished by attrition.

It is again an attack on the foundations of our constitutional order.

The Senate is an indispensable part of our legislative process.

Laws can't be passed without its scrutiny.

The Court in the Senate reference decision also pointed out it a necessary complimentary body to the House of Commons and in the partisan environment of the lower house a desperately needed chamber of sober second thought.

It is also critically intertwined with the other parts of the Constitution.

The floor of representation of each of the provinces in the House of Commons is the number of senators they have.

This is vital to all the population-challenged Atlantic provinces. They will not only fight any abolition, they should argue that Harper's refusal to appoint their quota of Senators is a gross violation of the Canadian constitution.

Quebec will no doubt follow suit.

The Senate is without one-fifth of the required number of members and by 2017 if no appointments are made by the prime minister it will be down to just 71 senators from the constitutionally required number of 105 and which can't exceed 113.

The ability of the Senate to be a complimentary body and do effective "sober second thought" legislative oversight in committees will be severely impacted.

Could Harper's latest attempt to play games with the Canadian constitution be just an attempt to change the channel due to the resumption of the most politically damaging part of the Duffy trial that will involve his former Chief of Staff, Nigel Wright and from the fact that the major part of the scandals in the Senate due to the appointments that he made despite his promise before being elected as PM that he would never appoint unelected senators?

The thrashing of the credibility of the Senate with Canadians is due to the individuals Harper and other PMs have appointed, not with the institution that was designed to represent the regions of the country.

Moreover, in an age of everything but the kitchen sink massive omnibus legislation often passed with limited time for debate due to closure, most MPs don't exercise any effective legislative oversight.

With the increasingly toxic and partisan environment in the House of Commons that Harper himself has created, we will increasingly need a functioning Senate with the RIGHT individuals who may actually do the job that the House of Commons is supposed to do.

It is indeed sad that two of the leaders of parties who are vying to be prime minister fail to understand this and are willing to engage in what is clearly unconstitutional actions.

--Professor Errol Mendes is a professor of constitutional and international law at the University of Ottawa and Editor in Chief of the National Journal of Constitutional Law.