The U.S. Supreme Court on Monday vacated a lower court’s temporary restraining orders which had prohibited the Trump administration from deporting Venezuelan migrants through its unprecedented invocation of the Alien Enemies Act of 1798.

While all nine justices agreed that any individual detained under the wartime authority must be afforded notice and due process of law — a clear setback for Trump’s plan to fast-track removals — the most surprising vote was cast by Justice Amy Coney Barrett, who once again threw her lot in with the court’s liberal bloc by joining parts of Justice Sonia Sotomayor’s dissent. It is not the first time the Trump-appointed justice had spurned the court’s conservative block — a point that was not lost on the MAGA faithful who cheered her nomination years ago.

In the 5-4 decision on the emergency application, the court ruled on procedural grounds. The majority held that the five Venezuelan plaintiffs should have brought their case as individual habeas corpus petitions in Texas, where they are being held, not Washington, D.C., where they originally filed the class action suit under the Administrative Procedures Act (APA). Habeas petitions involve detainees challenging the legality of their custody and typically seeking to be released.

In a scathing dissent, Sotomayor excoriated the Trump administration for failing to comply with court orders and ignoring its “obligations to the rule of law” and harangued the majority for even intervening in the case at all, saying the decision was “as inexplicable as it is dangerous.” But Barrett shrewdly avoided joining the more harshly-worded portions of Sotomayor’s dissent, only joining the most senior liberal justice in parts II and III-B.

Part II briefly reiterates that all migrants are entitled to due process prior to removal under the AEA, largely agreeing with the majority on the constitutional issue.

In part III-B, Sotomayor asserts the majority’s conclusion that challenges to removals under the AEA must be filed as habeas petitions is “dubious.” She emphasizes that habeas corpus is “at its core, an avenue for a person in custody to ‘attack … the legality of the custody’ and ‘to secure release from illegal custody.”” However, the plaintiffs in this case did not challenge their detention, they only sought “to protect themselves from summary deportation.”