Radical Democrats have begun demanding that their party’s nominees pledge to “pack” the Supreme Court, if elected, by appointing left-wing judges to offset the current conservative majority. An obvious precedent for this strategy is Franklin Roosevelt’s threat to pack the court in the 1930s, which seemingly caused some justices to begin approving constitutionally questionable New Deal measures.

There is another historical precedent that I find more suggestive. In the late Stuart era, when the House of Lords was more powerful than in recent times, the Tories and Whigs successively found themselves in control of the House of Commons, but blocked by the Lords. Since the House of Lords has no fixed number, each responded by procuring the appointment of a group of new peers who were sympathetic to its positions. Thus did the British peerage expand.

The concept of packing the House of Lords didn’t go away. In 1832, during the great debate over the first Reform Act, the Whigs brought the threat of Lords-packing to bear:

The Bill was passed due to Lord Grey’s plan to persuade King William IV to consider using his constitutional powers to create additional Whig peers in the House of Lords to guarantee the Bill’s passage. On hearing of this plan, Tory peers abstained from voting, thus allowing the Bill to be passed but avoiding the creation of more Whig peers.

While the House of Lords exerts much diminished powers today, packing it remains a viable strategy:

Theresa May is expected to approve the creation of about 10 Conservative peers and at least one for the Democratic Unionist party, perhaps as early as Friday, in an attempt to improve her position in the House of Lords, which has voted 15 times against her government over Brexit.

The U.S. Supreme Court, like the House of Lords, has no constitutionally fixed number, although longstanding tradition has put it at nine members. What will happen if a Democratic president packs the court to give it a left-wing majority? For one thing–a fact Democratic activists seem to be overlooking–the next Republican president will engage in his own court-packing, so as to re-create a conservative majority.

There is, I think, a strong parallel between Britain’s House of Lords and the liberal view of the Supreme Court. Liberals see the Court as essentially legislative in nature, like the House of Lords. The Court’s function is not primarily to decide cases like a normal judicial body, but rather to pronounce on social policy.

Further, in liberal eyes the Supreme Court is meant to represent America’s elites, just as the House of Lords represents Britain’s. Our elite is not mostly hereditary, of course; but if you substitute urban, coastal, well-educated, likely a lawyer, and liberal for Earl or Viscount, you identify a class that is just as self-conscious, and far more power-hungry, than Britain’s hereditary elite.

Liberals see the Supreme Court much as the British have traditionally seen the House of Lords: as an elite check on the excesses of democracy. For liberals, the Court exists to strike down ill-conceived legislation that goes against the liberal consensus of the moment, as, for example, a ban on late-term abortion. Similarly, the Court exists to enact liberal social policies that benighted voters are not willing to approve, like universal gay marriage.

Packing and counter-packing the Supreme Court would inevitably transform that institution into something it was never meant to be, but which liberals think it already is–a super-legislature that represents the views and interests of America’s governing classes, in contrast to those of plebeian voters. In other words, something much like Britain’s House of Lords, back when that body exercised great constitutional powers.

The Founders would be shocked to learn that in the 21st century, American “progressives” are trying to create something like their very own House of Lords.