There might not be a problem with nationwide injunctions.
However, as argued by the the United States in Trump v. CASA, Inc., the main issue is that universal injunctions improperly grant relief to non-parties (see Brief of the United States). In brief summary, they argue that (see pages 16-20):
- nationwide injunctions exceed the power of Article III courts (by straying beyond the case or controversy actually before the court);
- conflict with longstanding limits on equitable relief; and
- they operate asymmetrically — "granting relief to strangers everywhere whenever a single plaintiff prevails, but not precluding continued litigation by others if some plaintiffs lose".
These and related issues were also raised by Samuel L. Bray in his 2017 article, "Multiple Chancellors: Reforming the National Injunction" (2017) 131:2 Harvard Law Review. In addition to the above to problems, Bray argues that:
- national injunctions incentivize forum shopping
- national injunctions risk conflicting injunctions
- national injunctions alter judicial decision-making by preventing a potential divergence of views from developing among the circuits
You ask:
How are lower courts supposed to address policies like this without broad injunctions?
The critics' answer would be that courts are not supposed to address policies. Courts may only decide the discrete case or controversy presented to them as between the parties in the individual case.
You ask:
Is it really envisioned that the policy should be addressed on a case-by-case basis? I've seen mention in some news articles that the way to get a broad ruling is with a class action suit.
This is exactly what Bray proposes (at p. 475):
Admittedly, there may be cases in which an injunction protecting
only the plaintiff proves too narrow. But in such cases there is an obvious answer: a class action.
As does the government:
Affected individuals could instead seek class certification and, if appropriate, seek class-wide preliminary relief.
You ask:
Can nationwide injunctions only be issued by SCOTUS?
The United States' position is that not even the Supreme Court of the United States can issue a nationwide injunction. Instead, when the Supreme Court rules that a law is unconstitutional, that holding is binding on all courts as a matter of stare decisis as opposed to an order that literally binds the United States with respect to all parties. The United States would be unable to enforce that unconstitutional law against anyone because all challenges against the law would immediately be successful. See the Brief of the United States, p. 19.
There are of course counterarguments, but as you have asked what the problem is, I only present what some view as the problems.
