A 6-3 majority of the U.S. Supreme Court has placed a stay on the US Occupational Safety and Health Administration's COVID-19 vaccination-or-testing mandate for employers with 100 employees or more, including those in the construction sector.

All justices appointed by Republican presidents—Chief Justice John Roberts and Justices Clarence Thomas, Samuel Alito, Neil Gorsuch, Brett Kavanaugh and Amy Coney Barrett—joined the unsigned majority opinion that said "no provision of the [1970 Occupational Safety and Health] Act addresses public health more generally, which falls outside of OSHA’s sphere of expertise."

In deciding that contractors and other large employers won't have to mandate that their workers either get vaccinated against COVID-19 or submit to weekly testing by an OSHA deadline of Feb. 9, the majority opinion stated that businesses and states who filed lawsuits against the agency's November emergency temporary standard are likely to prevail in the lawsuit, which was sent back to the Cincinnati appellate court to be heard in full.

"The applicants are likely to succeed on the merits of their claim that the Secretary [of Labor] lacked authority to impose the mandate," the unsigned opinion said. "Administrative agencies are creatures of statute. They, accordingly, possess only the authority that Congress has provided. The Secretary has ordered 84 million Americans to either obtain a COVID–19 vaccine or undergo weekly medical testing at their own expense. This is no 'everyday exercise of federal power.'"

The justices wrote that the OSH Act plainly does not authorize such action.

The Associated Builders and Contractors of America, which joined the lawsuit against the OSHA standard and also filed suit against a separate federal contractor mandate, immediately celebrated the ruling.

“ABC is pleased that the Supreme Court blocked OSHA’s COVID-19 vaccination and testing ETS," Ben Brubeck, ABC vice president of regulatory, labor and state affairs, said in a statement. "This is a big win in removing compliance hurdles for the construction industry, which is facing multiple economic challenges, including a workforce shortage of 430,000."

Brubeck said that ABC supports vaccination and pointed contractors to a toolkit on its website.

Justices Stephen Breyer, Elena Kagan and Sonia Sotomayor wrote, in a dissenting opinion, that the ETS is necessary to address the danger of COVID–19 and that OSHA based its rule, requiring either testing and masking or vaccination, on a host of studies and government reports showing why those measures were of use in limiting the threat that COVID–19 creates in most workplaces.

The majority opinion responded to the dissent, saying that the authority to make such a broad standard is outside of OSHA and U.S. Dept. of Labor purview, especially because all workers who are vaccinated in the workplace would also have to be vaccinated outside of it.

"The dissent protests that we are imposing 'a limit found no place in the governing statute," the majority wrote. "Not so. It is the text of the agency’s Organic Act that repeatedly makes clear that OSHA is charged with regulating 'occupational' hazards and the safety and health of 'employees.'"

The majority also pointed out that the only two exemptions in the rule, one for workers who work entirely outside and one for workers who work in the home, were not tailored to specific occupations and that even landscapers who entered an office for a few minutes a day would not be covered by the exemption for workers who who work entirely outdoors.

Contractor groups such as ABC and the Associated General Contractors of America argued in their briefs that a broader exemption for construction sites that are mainly outdoors should be considered by the agency.

"There is good reason to expect the administration’s OSHA vaccine mandate will not pass legal muster and pausing it now will protect countless firms from the inevitable harm the mandate will cause," says Brian Turmail, AGC vice president of public affairs and strategic initiatives. "Moving forward, we will focus on ensuring our legal challenge is successful. In addition, we will continue our efforts to encourage more workers to get vaccinated."

He added that AGC will soon release a set of Spanish-language public service announcements in major construction markets to complement those in English released last year.

U.S. Labor Secretary Martin Walsh (D) said in a statement that he was disappointed by the ruling and that the department urges "all employers to require workers to get vaccinated or tested weekly to most effectively fight this deadly virus in the workplace."

He did not mention next steps or what OSHA will do now that implementation of some measures of the mandate, such as required masking of unvaccinated workers, began on Jan. 10.

A spokesperson for OSHA did not immediately respond to messages about the agency's next steps.