The constitutional architecture

The Constitution Act 1867 (formerly the British North America Act) divides legislative authority between Parliament (federal) and the provincial legislatures. The principal allocation is in ss.91 and 92.

Section 91 lists Parliament''s exclusive legislative powers (criminal law, defence, currency, banks, trade and commerce — and the residual peace, order and good government).

Section 92 lists exclusive provincial powers (property and civil rights, administration of justice, municipal institutions, hospitals).

Other sections allocate further matters: 92A (natural resources), 93 (education), 94A (old age pensions), 95 (agriculture and immigration — concurrent), 96 (judicature appointments).

How conflicts are resolved

Pith and substance. The court determines the dominant character of the impugned legislation, then asks under which head of power it falls. Incidental effects on the other order''s jurisdiction are tolerated.

Double aspect. Some matters can be regulated from both federal and provincial perspectives. Drinking-and-driving is the classic example — federal Criminal Code provisions and provincial highway-traffic provisions both apply.

Paramountcy. Where federal and provincial laws conflict (operational conflict or frustration of federal purpose), federal law prevails.

Inter-jurisdictional immunity. A core of an exclusive head of power is immune from incidental impairment by the other order. Now narrow (Canadian Western Bank 2007) — applied only where impairment is serious.

Section 91 selected powers

Criminal law (s.91(27)). Broad — includes regulatory schemes with a criminal-law purpose (Margarine Reference; Firearms Reference).

General trade and commerce (s.91(2)). Narrow. The General Motors test: regulation of trade as a whole, general regulatory scheme, oversight body, provincial constitutional incapacity, failure of one province jeopardises the whole. Securities Reference (2011) struck a comprehensive federal Securities Act; the cooperative model (2018) survived.

Banks (s.91(15)). Federal. Provincial consumer-protection law generally applies to banks unless it impairs the federal banking core (Canadian Western Bank).

Peace, order and good government

The opening words of s.91. Three branches:

Gap branch (matters not assigned to the provinces; e.g. incorporation of federal companies).
Emergency branch (temporary federal jurisdiction during war, public-health emergency).
National concern branch (Crown Zellerbach 1988; refined in GHG Reference 2021): single, distinct, indivisible matter; impact reconcilable with division of powers; provincial inability.

The GHG Reference (2021) reinvigorated the national-concern branch: minimum federal carbon-pricing standards are a matter of national concern.

Section 92 selected powers

Property and civil rights (s.92(13)). The largest provincial power. Contracts, tort, property, family, succession, regulation of trades and professions.

Administration of justice (s.92(14)). Provincial courts and procedure. The federal Crown sets criminal substantive law (s.91(27)) but provinces administer the courts.

Local works and undertakings (s.92(10)). With exception 10(a)–(c) for works connecting provinces or declared to be for the general advantage.

The judicial architecture

Section 96 reserves federal appointment for superior-court judges. Provincial-court judges are provincially appointed.

The provinces cannot create courts whose jurisdiction equates to that of s.96 superior courts (the Reference re Residential Tenancies and successor cases). The Trial Lawyers test refines.

Cooperative federalism

Modern doctrine (Quebec v Canada 2018; Securities Reference 2018) emphasises cooperative federalism — the constitutional space for federal-provincial coordination where neither order alone has full competence.

Constitutional amendment

Part V of the Constitution Act 1982 sets out the amending procedures:

s.41 (unanimous consent — affecting fundamental institutions).
s.38 (general procedure, 7/50 — most amendments).
s.43 (bilateral, federal + affected province).
s.44 (Parliament alone — federal executive matters).
s.45 (legislature alone — provincial constitutional matters).

Senate Reform Reference (2014) confirms the architecture-not-just-text approach to amendment.

A worked analytical sequence

Identify the law (or proposed law).
Determine pith and substance (purpose + effect).
Identify the head of power.
Address double aspect, paramountcy, IJI as needed.
Project to the appropriate amending procedure if reform is in issue.