ICYMI: Trudeau 2.0 swept to power with a new majority government on Monday evening (October 19).

Justin Trudeau made a number of lofty promises that are unprecedented in Canadian politics, should he actually follow through on them. That’s perhaps most evident in his promises to legalize marijuana and to reform our first-past-the-post electoral system.

The former is probably good policy and good politics. Virtually every poll suggests that the majority of Canadians favour marijuana legalization. Law enforcement experts such as police, prosecutors, and former politicians, widely view the "war on drugs" (dating back to Nixon, who was the first to declare outright war—a curious parallel with our soon-to-be former PM's views on the matter) as an outright failure, the same way alcohol prohibition was in the U.S.)

Legalizing the drug will divert law enforcement resources to more pressing matters, such as investigating violent, exploitative crimes and growing cyberfraud. It will also raise tax revenue to invest in infrastructure instead of that money going to drug dealers' pockets. Youth access to the drug is also likely to become more difficult.

The legal mechanisms of regulation vary widely. The federal government, which prohibits the drug through the Controlled Drug and Substances Act, could simply remove the prohibition, leaving the provinces to fill the vacuum. It might be difficult for the federal government to exercise outright regulatory jurisdiction over it, as that might fall to the provinces in the same way alcohol and tobacco do. That’s because the primary, if not exclusive, basis for the federal government's jurisdiction is its criminal authority, which typically requires an outright prohibition as opposed to regulation.

Another option would be to maintain the prohibition, but create an exception for provinces or territories that choose to establish regulatory regimes for marijuana. The federal government could establish health and safety requirements and import/export controls, as occurs with food and medicine, leaving taxation and day-to-day regulation (e.g. minimum age for consumption) to the provinces.

The last, and likely most complex, would be for the federal government to set up its own regulatory structure. That might be expensive and ripe for failure, in that the provinces have existing, tested systems and expertise to enforce regulation given their backgrounds in alcohol and tobacco. It might also invite legal challenges from the provinces who would want to collect taxes or from violators charged with offences seeking to have the legislation declared unconstitutional, as has happened with federal environmental legislation in the past.

Electoral reform is another matter altogether. A comprehensive analysis of the many legislative and constitutional issues underlying our electoral system is beyond the scope of this piece. That said, we may run into many of the same issues that plagued outgoing Prime Minster Stephen Harper's attempts at senate reform.

There, the Supreme Court of Canada held that a change to the senate required the government to follow the constitutional amendment formula set down in the Constitution Act. Harper, lacking the vision and wherewithal to pursue an agreement over the issue with the provinces, threw up his arms and, unsurprisingly, implicitly blamed the courts for insisting that he adhere to the rule of law. (When he decided to simply stop appointing senators, an arguably illegal move, a brave B.C. Hydro lawyer named Aniz Alani took him to court. The matter is pending).

Would the same be required for a change to our electoral systems? Arguably, yes.

Certainly, I think we have to expect legal challenges to whatever is proposed. In Canada, our constitution is not just a foundational document (as in the U.S., where America’s constitution is entirely based on legislation). We follow the British tradition, wherein the "constitution" of our country is found in a variety of legislative documents and traditions or customs (in particular the role of the Crown). The Supreme Court of Canada has also found that there are "unwritten" constitutional principles that emerge based on changing times and traditions.

A simple example is the impact that electoral reform would have on riding boundaries.

Some ridings are guaranteed perpetual existence (e.g. some ridings in the Eastern Townships of Quebec). The purpose behind this is to ensure that different regions will always have representation in the House of Commons. While proportional representation would not change the boundaries themselves, it could result in some ridings not sending any representative to Ottawa. Such an outcome would be unprecedented in Canadian politics.

While national parties like the Green Party would benefit by sending more representatives to Ottawa, the Bloc Quebecois would probably see its power diminished, unless some mechanism was put in place to preserve what is essentially the desire of regional voters to be represented by a party focused on their region's issues. I say so despite being a born-and-bred Anglophone Quebecker who grew up there during some of the worst times for separatism in Canadian history. I have no desire to see a strong sovereigntist party anywhere, but do respect voters' autonomy to have their particular views represented by a candidate or party of their choosing. Proportionate representation might mean that a party in rural Quebec who votes strongly in favour of the Bloc being represented by a candidate from an urban centre, whose views might diverge significantly from that of the constituents who actually voted them into power.

Much remains to be seen of this greenhorn PM. He is the first Liberal prime minister to be elected without having sat in cabinet. (Meanwhile, Brian Mulroney and Harper are two recent examples of Tory prime ministers who had no cabinet experience.) Trudeau’s policies and platform were geared toward a younger, millennial electorate in much the same way that Obama's 2008 campaign was. While Trudeau will not face the same partisan hurdles that Obama has in their legislative assemblies as a result of his parliamentary majority, he is proposing dramatic overhauls, many of which have constitutional or legal implications that might parallel the court challenges Obama has faced in his tenure.

Michael McCubbin operates a busy litigation practice in downtown Vancouver, focusing on criminal, constitutional, and administrative law. Reasonable Doubt appears on Straight.com on Fridays. You can send your questions for the column to its writers at straight.reasonable.doubt@gmail.com.