I'm not a constitutional scholar, so take with a grain of salt, but in a nutshell, without a 'Constitution' which broadly codifies rights, then laws are interpreted more narrowly - government has more flexibility to 'enact laws'.

But when there is a 'Constitution' that sets a broad but vague boundaries (Canada got one in 1982), then the Courts have significantly more power to interpret laws through the lens of Constitutionality.

After Canada got a proper Constitution in 1982, a bunch of laws that were on the books were overturned by the Canadian Supreme Court.

So things like abortion, civil rights, gay marriage, euthanasia etc. ... we don't actually 'legislate' these things - even if we do - the 'actual rules' are basically going to be determined in the Supreme Court.

Euthinasia is allowed in Canada, not because we legislated it, but because there was a Supreme Court ruling [0] in 2015, which kind of 'flip flopped' on a previous ruling a decade before.

This is from the CBC [1] which articulates some of the changes. In this article they talk mostly about 'human rights' which is good obviously (but you have to think about framing bias). Most conspicuously, they note in the last section the rise of 'Judicial Activism' - kind of an American term, and kind of loaded so a lot of people don't take to it very well, but what they mean is 'more freedom of the courts to interpret the law'.

i.e.

"amounts to a significant transfer of policy making to the courts," especially in an area that could be described as "morality issues."

"The charter has meant that the courts have a major influence on those things in a way they wouldn't have previously," he says.

Some would argue that this is 'how it should be' and that previously there was Parliamentary Supremacy ... except that I do believe something is fairly wrong when we really have no clue if the laws we write are constitutional or not. That makes absolutely no sense.

The courts don't write the laws, but they're ultimately the deciding factor on all the huge issues.

I don't believe that Constitutionality should be the purview of the courts, since it kind of implies they set their own jurisdictional bounds.

In my view - the Courts should only be able to interpret the law as is. If there is a major Constitutional review - that it might get deferred to a different body or process. I don't know what that would be. But not the Supreme Court in the way that it works today.

This is a global phenomenon because a lot of 'new' constitutions are being written.

It's not talked abut a lot, but it's one of the major behind the scenes issues around Brexit.

The EU (as the EEC) established a court called the 'European Court of Justice' (ECJ).

It was never agreed to in treaty that it's laws would be 'supreme' to those of nation states.

But - in hugely impactful ECJ ruling in 1964, the ECJ basically made a constitutional assertion: "Since we have formed a union, and act like one, and since we are the court of he union, then our rulings have supremacy over national courts".

What that means is - the ECJ ruling on a fairly minor case (with huge implications) decided their own jurisdiction: they were the 'Supreme Court' of Europe, and their laws trumped national laws.

Consider how crazy that is: EU leaders never actually explicitly agreed to that. Don't you think, that if your nation was going to enter into a treaty with other nations, and that you're going to hand over a fundamental pillar of sovereignty' - that this would be explicit* and clear in the treaty? With a bunch of parameters? And a referendum?

So who has 'Supreme Power'? The ECJ? Because they said so?

Over time, it's an issue that makes it's way through the various national legal systems. In some countries (France) it's more established. In others, not so much. But there have been further EU treaties since then so it effectively becomes more 'codified' indirectly.

The Germans maintain a kind of 'backstop' to this, in that they believe they have the right to review EU laws in a certain way, and that their Constitution is 'inviolable' but it's still kind of 'up in the air'.

This comes back to the 'Constitutional' issue in an important way since the EU has established their 'Charter of Fundamental Human Rights' [3] - which codifies more strongly all the 'nice human rights things' - with the caveat that the wording is naturally very vague, and gives the courts enormous power over established law.

It wasn't talked about much, but the ambiguity of all of this, and particularly the ECJ's interpretation of this new Charter, mean that there was a kind of 'unspoken war' brewing between UK Courts and the ECJ that was going to happen basically over decades of proceedings. This is partly because the UK doesn't have a formal Constitution with all the 'nice rights' in 'clean, nice sounding paragraphs' etc..

Basically, it's a giant paradox. Everyone wants 'human rights and constitutional protections', but they're generally fairly vague and aspirational documents that some arguably put the entire legal system up for grabs by the institution that has (or 'takes') the power to do it. However much oversight, there's a kind of a back door mechanism to incredible power.

When we say 'Western Liberal Democracy' we usually mean Executive, Legislative and Judiciary with 'equal' powers - the balance of power to stop authoritarianism. (In reality you could throw in the Central Bank and 'free press' as being just as important).

So it's not a small, petty debate, it's kind of foundational material. It's a really big deal.

Finally: huge grains of salt here, I'm not an expert, just a casual observer. I reserve the right to be fully corrected by the many lawyers here on HN.

[0] https://www.justice.gc.ca/eng/cj-jp/ad-am/scc-csc.html

[1] https://www.cbc.ca/news/canada/6-big-changes-the-charter-of-...

[2] https://en.wikipedia.org/wiki/Primacy_of_European_Union_law

[3] https://en.wikipedia.org/wiki/Charter_of_Fundamental_Rights_...