“The Court concludes that the CAA may indeed embrace the conservationist interests that Plaintiffs seek to protect,” McFadden wrote in his 59-page decision.

McFadden’s decision is notable because he concluded last June that the House lacked standing to use the courts to try to block the same disputed spending — part of an $8 billion plan Trump announced in February 2019, after getting just $1.3 billion from Congress for border wall spending in heated budget negotiations. Trump also declared a national emergency and argued that it authorized some of the expenditures.

“While the Constitution bestows upon members of the House many powers, it does not grant them standing to hale the executive branch into court claiming a dilution of Congress’s legislative authority,” McFadden wrote then.

The ultimate impact of McFadden’s ruling is uncertain. He has not yet ruled on whether the Trump administration’s spending was illegal, solely that the groups may press on with their suits challenging it.

Other federal judges in California and Texas issued orders blocking aspects of Trump’s border wall funding plan, saying it appeared to usurp Congress’ authority over federal spending. However, those injunctions were put on hold by the Supreme Court and a federal appeals court.

The House appealed McFadden's earlier ruling to the D.C. Circuit Court of Appeals. A three-judge panel there heard arguments on the case in February, but the court announced last month that a larger, en banc panel of the court's judges will decide the matter. A new round of arguments before that group of judges is set for later this month, but it is unclear whether those will take place as scheduled because of the ongoing coronavirus pandemic.