Supreme Court Chief Justice John Roberts questioned the limits of Congress's power to change the law in ways that affect ongoing lawsuits.AP Photo/Evan Vucci

Supreme Court Chief Justice John Roberts was skeptical Wednesday of Congress’s attempt to give the victims of Iranian terrorism a leg up in their lawsuits against the regime.

On their face, Congress’s actions might not seem too controversial: For years, Iran had refused to pay court-ordered judgments to the American victims of bombings in Lebanon and Saudi Arabia. So, when those victims found out that Iran had secretly stashed nearly $2 billion in a U.S. bank, Congress passed a law to help the victims claim that money as part of their lawsuit against Iran. President Obama signed it. And other than Iran, everyone was happy.

On Wednesday, however, Roberts expressed concern over how far Congress can venture into the judicial realm. If Congress can meddle in a specific lawsuit against Iran, he asked, what’s to stop it from trying to tell the Supreme Court how to rule on Obamacare?

He didn’t get an answer to that question that he found satisfactory, and his underlying concern about separation of powers was a critical thread throughout an hour of oral arguments in Bank Markazi v. Peterson, in which the Iranian central bank is arguing that Congress’s intervention violated the Constitution.

“You know, there are places in the world where courts function just the way our courts do, except every now and then, when there's a case that the strongman who runs the country is interested in because a crony is one of the parties or whatever, and he picks up the phone and he tells the court, ‘You decide this case this way. I don't care what you thought the law was, decide it this way,’” Roberts said. “I’m not sure I see what the difference is here.”

The law Congress passed is very specific. It even gives the case number for the victims’ lawsuit, saying the assets identified in that case are “sub­ject to ex­e­cu­tion … in or­der to sat­is­fy any judg­ment … awar­ded against Ir­an for dam­ages for per­son­al in­jury or death caused by an act of [ter­ror­ism].”

The Supreme Court previously said Congress can change the underlying law in a way that affects ongoing cases—for example, by changing a statute of limitations—but can’t dictate the outcome of a particular case. The question for the court is which of those things happened here, and where to draw the line between the two.

Defending the anti-Iran law Wednesday were Theodore Olson, a former Bush administration solicitor general representing the plaintiffs in this case, and Deputy Solicitor General Edwin Kneedler. They told the court that Congress had simply changed the underlying law about the execution of assets held by a foreign country. And the fact that the change only applied to one case is not a problem, they said, because the actual change was still a change in the law.

Does that mean, Roberts asked, that Congress could, for example, pass a law directing the Supreme Court to accept the Health and Human Services secretary’s position in cases challenging a health care law? Olson allowed that it might.

“What happens if, rather than just picking the winner, Congress amends the law, tweaks the law, modifies the law in such a way—as to only this case—that it's absolutely clear that the effect of that will be to pick a winner?” Justice Elena Kagan asked Kneedler.

“I think if Congress is amending the law, it can do that,” Kneedler replied.

Roberts saw that as a distinction without a difference.

“You're saying Congress has to be cute about it,” he said. “They can't say 'Smith wins'.  But they can say in the case of Jones v. Smith where the critical issue is this, we can change that in a way so Smith wins. And don't worry about the law generally, because it's just this case. It’s a cute way of saying, ‘Smith wins.’”

All told, Wednesday’s arguments did not offer a strong indication of which way the Court is likely to rule. Oral arguments often provide only a rough guide to the justices’ thinking, and they frequently press certain points either as an intellectual exercise or to test the limits of a position they’re actually inclined to agree with.

The Court’s liberal justices offered several reasons why Congress might have acted well within its authority. The courts generally give the elected branches reasonably wide latitude on matters of foreign policy, and Congress often intervenes in individual cases through “private bills.” They also questioned the limits of Iran’s assertion that Congress singled out “one case and one case only.” What if it were 10 cases, they asked, or 100?

Roberts, though, said he didn’t understand “the fixation on how many cases we’re talking about.” The issue, he said, was the action Congress took, and whether it encroached on the courts’ turf.

“Our job is to decide cases,” Roberts said. “Their job is to pass laws, our job is to decide cases.”

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