Friday night's 5-4 decision allows construction to continue during the ongoing legal battle. The ruling came along party lines, with the court's four liberal justices offering their dissent.
In the direct, three-sentence dissent, Justice Stephen Breyer wrote, quoting a 2019 ruling, "Just over a year ago, I suggested 'a straightforward way' to avoid irreparable harm to the parties in this litigation: stay the District Court’s injunction 'only to the extent' that it 'prevents the Government from finalizing [relevant] contracts or taking other preparatory administrative action, but leave [the injunction] in place insofar as it precludes the Government from disbursing those funds or beginning construction.'"
He added, ominously, "Now, the Government has apparently finalized its contracts, avoiding the irreparable harm it claimed in first seeking a stay. The Court’s decision to let construction continue nevertheless, I fear, may 'operat[e], in effect, as a final judgment.'"
Members of the Sierra Club and Southern Border Communities Coalition first challenged Trump's use of a national emergency declaration last year.
"The fight continues," said attorney Dror Ladin of the American Civil Liberties Union, which represents the environmental groups in the case. "Every lower court to consider the question has ruled President Trump's border wall illegal, and the Supreme Court's temporary order does not decide the case."
"We'll be back before the Supreme Court soon to put a stop to Trump's xenophobic border wall once and for all," Ladin continued. "The administration has admitted that the wall can be taken down if we ultimately prevail, and we will hold them to their word and seek the removal of every mile of unlawful wall built."
The southern border wall has been a hallmark of Trump's platform since the very beginning of his 2016 campaign. The then-candidate promised repeatedly at campaign events that he would build a wall along the entirety of the U.S.-Mexico border and Mexico would pay for it.
"Build the wall" became a common chant at Trump political rallies on the campaign trail in 2015 and 2016.
Ex-Mexican President Enrique Peña Nieto and current President Andrés Manuel López Obrador have each condemned the wall and said the country would not provide any money. But Trump has continued to pursue building the wall throughout his 3 1/2 years in office.
Very little new wall construction has actually taken place. The administration celebrated the completion of 100 miles of construction in January, but most of what's been completed thus far has been replacements of the smaller barrier designs that were constructed with decades-old technology. Trump visited the border in late June to celebrate 200 miles of construction even as the administration has shifted focus to the coronavirus pandemic. Trump has promised 450 miles of wall by the end of the year.
The U.S.-Mexico border is about 2,000 miles long.
The Sierra Club and Southern Border Communities Coalition both vowed to continue the fight Friday night.
"This fight is far from over and we will continue to stand alongside the ACLU and the Sierra Club to fight for our democracy and our communities that are suffering from unaccountable and harmful border policies," Vicki B. Gaubeca, director of the Southern Border Communities Coalition, said in a statement. "We don’t need more irresponsible walls at our borders, we need more responsible border governance that begins with respecting the checks and balances in this country. We need a New Border Vision that expands public safety, protects human rights, and welcomes all people to our region."
"Border communities and ecosystems are suffering irreparable harm, but the Sierra Club will never stop fighting this disastrous project," Gloria Smith, managing attorney at the Sierra Club, said in a statement after the Supreme Court ruling.