The court in New York blocked a memorandum signed by the president in July, which instructed the Census Bureau to calculate apportionment counts without including undocumented immigrants. The judges ruled that the plan would violate a statute on congressional apportionment.

The apportion base establishes the number of members each state receives in the House of Representatives.

The judges wrote: “Congress mandated that the president use a specific set of numbers — those produced by the decennial census itself — for purposes of the reapportionment. By deviating from that mandate, the presidential memorandum exceeds the authority of the president.”

The judges were acting on two lawsuits filed by a group of states, cities and civil rights groups. The ruling is expected to be appealed in the Supreme Court.

The Census Bureau is due to end its census operations at the end of September, a month earlier than previously planned as part of an extended timeline in response to Covid-19, however, a federal judge recently ordered the bureau to stop winding down its operations until a court hearing is held on 17^th September.