A federal judge on Friday issued a preliminary injunction blocking the Trump administration’s plan to implement a procedure that would expedite the deportation process of undocumented immigrants.

This policy was initially used to deport individuals who entered the US without a hearing before an immigration court judge. In July the Department of Homeland Security expanded the rule to include undocumented immigrants who could not provide proof that they have resided in the country for two or more consecutive years.

US District Court Judge Ketanji Brown Jackson ruled that the changes to the policy were arbitrary and capricious:

Put in common parlance, if a policy decision that an agency makes is of sufficient consequence that it qualifies as an agency rule, then arbitrariness in deciding the contours of that rule—e.g., decision making by Ouija board or dart board, rock/paper/scissors, or even the Magic 8 Ball—simply will not do. There are well-established legal constraints on the manner in which an agency exercises its discretion to make discretionary policy decisions, and there are also legally established consequences if an agency does not adhere to these procedural requirements when it determines the policies that it imposes.

The preliminary injunction was sought by the American Civil Liberties Union, American Immigration Council and Simpson Thacher & Bartlett LLP.

The court banned implementation of the expanded expedited removal policy while the action against Department of Homeland Security proceeds.