A recent decision of the UK Supreme Court, R (SC) v Secretary of State for Work and Pensions,  UKSC 26, might be of interest for Canadian readers. Lord Reed’s judgment for the Court addresses issues that are relevant to current Canadian debates about the relationship between courts, legislatures, and rights, equality rights in particular. To be sure, the UK context is not the same as Canada’s. Still there are lessons to be learned there.
In a nutshell, at issue in SC was a statutory rule providing that one particular tax credit available to low-income families would only be payable in respect of a first and second child, but not for any subsequent children in a family. (Other benefits remained unaffected.) This was alleged to constitute discrimination, on a number of different grounds, in the protection of a right to family life, which is guaranteed by the European Convention on Human Rights, and thus by the Human Rights Act 1998. The Supreme Court found that there was indeed prima facie discrimination against women (who were more likely to be caring for multiple children) and children living in families with three or more children, as opposed to those living in smaller ones. But the rule was still justified as a reasonable means of ensuring the fiscal sustainability of the credit programme.
One could make many interesting observations about this. Canadian readers might want to consider the different approach to equality rights under the Convention and under s 15 of the Canadian Charter of Rights and Freedoms ―no abstruse inquiries into human dignity, histories of stereotyping, and so on, and a ready recognition of what we’d term “analogous grounds”, but also a greater willingness to defer to Parliamentary judgment, except where some particularly invidious forms of discrimination are concerned. But in this post I focus on a different issue: namely, Lord Reed’s comments on the nature and scope of Parliament’s engagement with rights, and the courts’ consideration of this engagement in assessing the compatibility of resulting legislation with the Convention.
These comments are part of Lord Reed’s discussion of “the use which can be made of Parliamentary debates and other Parliamentary material when considering whether … legislation is compatible with Convention rights”.  This was necessary because the parties argued about whether or not Parliament gave sufficient consideration to “matters which were argued to be relevant to the proportionality of the legislation, such as its impact upon the interests of the children affected”.  Lord Reed, however, cautions about this kind of argument, both out of respect for Parliament’s privileges and, no less importantly, in light of Parliament’s distinct constitutional role.
Parliamentary privilege, as part of the separation of powers, means relevantly “that it is no part of the function of the courts … to exercise a supervisory jurisdiction over the internal procedures of Parliament”.  In particular, courts should not expect and must not demand “transparent and rational
analysis” of rights claims by Parliament, because this “would be liable to make the process of resolving political differences through negotiation, compromise and the exercise of democratic power more difficult and less likely to succeed”.  The quality of the reasons given by individual Members of Parliament, or even by Ministers, is not what is at issue when courts assess the effect of statutory provisions on rights or their justification and proportionality in a democratic society.
Another aspect of the separation of powers, Lord Reed points out, is the distinction between Parliament and government. Among other things, this means that “[a]s a matter of daily reality, ministers and party whips
have to negotiate and compromise in order to secure the passage of the legislation which the Government has promoted, often in an amended form.”  And it follows from this that “[t]he reasons which the Government gives for promoting legislation cannot therefore be treated as necessarily explaining why Parliament chose to enact it”.  Neither the government nor individual members can be taken to be speaking for Parliament. Its “will … finds expression solely in the legislation which it enacts”,  and its “intention … or (otherwise put) the object or aim of legislation, is an essentially legal construct, rather than something which can be discovered by an empirical investigation”. 
At most, Lord Reed says, courts inquire into “whether matters relevant to compatibility” between an impugned statute and Convention rights “were raised during the legislative process”, while “avoid[ing] assessing the adequacy or cogency of Parliament’s consideration of them”.  If they were, then ― regardless of the quality of these debates ― Parliament’s enactment may be entitled to an additional measure of deference. The converse, however, is not true: lack of Parliamentary consideration of the issues does not count against the statute.
Canadian courts need to take heed. The most egregious example of their failure to attend to the principles Lord Reed expounds is surely the one Maxime St-Hilaire and I have written about here: the first instance judgment in the Québec mosque shooter’s case, R c Bissonnette, 2019 QCCS 354 (since reversed in part by the Court of Appeal, and now under appeal at the Supreme Court). There, Professor St-Hilaire and I noted, the judge engaged in
play-by-play commentary on Parliamentary debate, praise for “[o]pposition members [who] did their job”,  denigration of a government member’s answer as being of “dubious intelligibility”  and of the Parliamentary majority as a whole for its “wilful blindness”  in the face of opposition warnings.
Another recent example is provided by Justice Zinn’s comments in Smith v. Canada (Attorney General), 2020 FC 629 to the effect that “[a] statement made by the Prime Minister at the time as to the intent of Parliament and its members ought to be accorded significant weight, if not considered conclusive on the issue of Parliamentary intent”. 
But even the Supreme Court has sometimes succumbed to such misguided reasoning, if in less extreme forms. Thus in R v Safarzadeh‑Markhali, 2016 SCC 14,  1 SCR 180, Chief Justice McLachlin, writing for a unanimous court, picked and chose among various purposes offered by the Minister who had promoted the legislation at issue, declaring one to be the real purpose of the statute and the others “peripheral”. This arguably crosses the line into “impeaching” Parliamentary statements, and certainly wrongly attributes a Minister’s supposed purpose to Parliament, to the detriment of the separation of powers and to the advantage of the executive over the legislature.
That said, two caveats are in oder. First, Lord Reed’s emphasis on the separation of the executive and the legislature may not always be appropriate in the Canadian context, at least outside of minority government situations. When one considers the law-making practices of some governments and legislatures ― notably, ubiquitous abusive omnibus legislation, or laws interfering with constitutional rights passed in a matter of days, it is difficult to maintain that the legislatures involved are anything other than inanimate rubber-stamps, quite devoid of any “will of their own”. More generally, Canadian legislatures lack certain features and institutions that serve to maintain the Westminster Parliament’s partial independence from the executive. But that doesn’t change the principle that courts should not attribute the executive’s purposes to the legislature. Partly, this is to avoid rewarding the executive for overwhelming the legislature; partly because, as Lord Reed says, it is not the courts’ place to assess the quality of legislative deliberation, and that includes the degree of its independence from the executive.
Second, Lord Reed’s discussion of deference ― both the narrow point described above, to the effect that Parliament’s consideration of an issue should reinforce curial deference to its choices, and what he says elsewhere in the judgment ― is also to be treated with the greatest caution in Canada. Lord Reed is judging in a constitutional system where Parliamentary sovereignty rather than constitutional supremacy is the ultimate principle. But, moreover, section 1 of the Canadian Charter requires any limitations on the rights it protects to be “demonstrably justified” (emphasis mine). The wording of the European Convention is a bit different ― it speaks (for example in article 8, which was at issue in SC) of limits “necessary in a democratic society”. Those readers ― and judges ― who, like me, attach importance to the words of constitutional texts may well think that the Charter‘s emphasis on demonstrable justifications calls into question the appropriateness of judicial deference to legislative choices, and especially of deference on no stronger a basis than the fact that the legislature turned its mind to an issue.
But judges are not the only Canadians who should take note of Lord Reed’s explanations. The proponents of the use of the Charter‘s “notwithstanding clause”, which allows legislatures to maintain in operation laws that are contrary to the Charter‘s guarantees, ought also to consider what Lord Reed says about the difference between courts and legislatures. Their argument is premised, in part, on the claim ― often asserted though seldom supported ― that legislatures will serve “as a forum where rights are debated, articulated and enacted” with “the thoughtful participation of the people themselves”, in the words of Joanna Baron and Geoffrey Sigalet in a post over at Policy Options. Lord Reed’s explanations show why this claim is unlikely to be true, or at least nearly as true as its proponents make it out to be.
Lord Reed points out that the way in which Parliament does its business does not require debate and articulation of rights, or any particular degree of thoughtfulness on the part of the people’s representatives, let alone the people themselves. He writes:
First … Parliament does not give reasons for enacting legislation: it simply votes on a motion to approve a proposed legislative text. There is no corporate statement of reasons, and the individual members of Parliament do not give their reasons for voting in a particular way. …
Secondly, the decisions which Parliament takes are not necessarily capable
of being rationalised in any event. In the first place, Parliament does not operate only, or even primarily, as a debating chamber. It is also a forum for gathering evidence, and for extra-cameral discussion, negotiation and compromise. Furthermore, the way in which members of Parliament vote will usually, but by no means always, reflect party policy, and may be influenced by the discipline imposed by the party whips. -
Lord Reed further explains that while the courts’ task is “the production of decisions arrived at by an independent and transparent process of reasoning”, Parliament’s is
the management of political disagreements … so as to arrive, through negotiation and compromise, and the use of the party political power obtained at democratic elections, at decisions whose legitimacy is accepted not because of the quality or transparency of the reasoning involved, but because of the democratic credentials of those by whom the decisions are taken. 
In other words, when Parliament makes a decision, including a decision that impacts or even directly concerns the rights of citizens, it need not act on the basis of reasoned deliberation. It is just as likely to be giving effect to the results of horse-trading or to the political tactics of the majority, its ministry, and its whips. Rights, or any other considerations, need not be articulated in any sort of intelligent fashion in this process. To be sure, sometimes they will be ― but this is no more than a happy accident. It cannot be the foundation of a constitutional theory, let alone the basis on which anyone should accept that their rights can be suspended by a political faction that holds them in contempt.
For all that Canadians like to think of themselves as open to learning from the constitutional law of other countries ― and despite some reservations I have on this score! ― I think that we do not do it nearly enough. There is indeed a great deal to learn out there, and not least from the courts that, to some, might seem passé ― those of the United States and the United Kingdom. SC is a good reminder of that.