A newly-ascendent doctrine the Supreme Court has used to strike down disfavored executive regulations is the so-called "Major Questions Doctrine". The MQD, in essence, says that we should not assume that Congress has legislated on issues of major social or economic importance unless it does so very, very clearly. This means that even where the plain statutory text seems to authorize presidential action, courts can still nullify it if they decide that Congress' language was not "clear" enough given the magnitude of the policy at issue.
For example, in NFIB v. OSHA, the Supreme Court invalidated the Department of Labor's vaccine mandate despite statutory text authorizing OSHA to issue emergency rules when necessary to protect employees against "grave danger from exposure to substances or agents determined to be toxic or physically harmful or from new hazards." COVID-19, of course, is an "agent" which poses "grave danger" to employees, so it would appear based on the plain language that Congress had authorized this course of action. But no, said the Supreme Court -- if Congress wanted to authorize OSHA issuing blanket rules covering essentially all employers across the entire economy, it needed to be even clearer than that.
Many critics have assailed the MQD as the Court abandoning textualism when it conflicts with conservative policy preferences. In response, conservatives have tried to argue that the doctrine can be reconciled with textualism because the MQD comports with how ordinary readers read texts. In the student loan case, Justice Barrett made a popular version of this argument:
Consider a parent who hires a babysitter to watch her young children over the weekend. As she walks out the door, the parent hands the babysitter her credit card and says: "Make sure the kids have fun." Emboldened, the babysitter takes the kids on a road trip to an amusement park, where they spend two days on rollercoasters and one night in a hotel. Was the babysitter's trip consistent with the parent's instruction? Maybe in a literal sense, because the instruction was open-ended. But was the trip consistent with a reasonable understanding of the parent's instruction? Highly doubtful. In the normal course, permission to spend money on fun authorizes a babysitter to take children to the local ice cream parlor or movie theater, not on a multiday excursion to an out-of-town amusement park….
Problem one with this defense is that it turns out Justice Barrett's intuitions may not be accurate. A new article actually empirically tested Justice Barrett's example and found that most respondents did not find the babysitter's actions to be unreasonable. Whoops. (Kudos to Ilya Somin for at least acknowledging that this study is countervailing evidence against his own affinity for the MQD).
But my problem with this analogy is a little different: is it really fair to characterize the President as akin to Congress' babysitter? The Executive and Congress are coequal branches of government. Their relationship is not as one-sidedly hierarchical as the parent who makes a one-off hire of a babysitter. If we adjusted the hypothetical so it was two parents, one leaving on a business trip and who tells the other "make sure the kids have fun this weekend!", I doubt anyone would find the choice of the stay-at-home parent to take the kids to an amusement park to be even remotely problematic.
Now, I'll concede a potential problem with the revised hypothetical: the relationship between two parents doesn't generally involve delegations of authority. Mom and dad both are generally authorized to make choices about the kids on their own initiative. By contrast, nominally under our separation of powers system the executive is only empowered to act upon authorization by Congress.
I'm not sure this objection fully holds, however, and in any event it can be easily traversed. It doesn't necessarily hold because -- as any couple knows -- lack of a formal hierarchy between spouses does not mean that it's impossible for there to be instructions and acrimony where they're not followed. If mom says "make sure the kids take a bath", and dad lets them get away with just running through the sprinkler -- well, woe is about to fall upon dad, and it'll be worse for him still if he comes back with "as a co-equal parent, I am equally authorized to make parenting decisions on my own initiative."
But even if we think the parent-to-parent relationship doesn't quite work, it still seems clear that the relationship between Congress and the President is still more distant from a parent and babysitter. So how about parent and grandparent. Take Justice Barrett's hypothetical, but it's grandma watching the kids for the weekend. Grandma, unlike dad, does only have delegated authority to look after the kids. But nonetheless, I think very few people would think that grandma's amusement park trip would be unreasonable or out-of-bounds. The fact that grandma is herself part of the family, and not some random acne-faced fifteen year old, makes a huge difference in terms of what should be deemed reasonable.
When Congress passes laws for the executive to enforce, it is not "delegating" power to some ad hoc temporary babysitter who may or may not ever be hired again for $20/hour plus tips. It is interacting with an intimate family member with whom it has a long-standing relationship that will continue across a multitude of cases into perpetuity. That sort of relationship, it seems to me, makes the MQD less feasible. That Congress wouldn't be presumed give some random stranger authorization to make "major" alterations to social or economic policy does not mean that Congress wouldn't be presumed to give the President of the United States such alterations -- particularly when we're talking about legislation that is by its nature inherently imbricated in issues of major social and economic concern (workplace safety, environmental protection, educational access, and so on).