The Department of Justice concluded in an opinion that federal law doesn’t prohibit public agencies and private businesses from requiring COVID-19 vaccines under the Food and Drug Administration’s emergency use authorization.

On July 26, the U.S. Department of Veterans Affairs, California, and New York City said they would require some of their government workers to get the COVID-19 shot or be tested weekly. Veterans Affairs, with the move, became the first federal agency to mandate the vaccine.

The Justice Department’s Office of Legal Counsel on July 26 wrote (pdf) that because access to COVID-19 vaccines is more commonplace, “numerous educational institutions, employers, and other entities across the United States” have said they will require some individuals to be vaccinated against the virus as a condition of employment, participation, benefit, service, or relationship.

“For instance,” it wrote, “certain schools will require vaccination in order for students to attend class in person, and certain employers will require vaccination as a condition of employment.”

The opinion, which noted that some have questioned the legality of such mandates, concluded that federal law concerning the FDA’s emergency use authorizations (EUA) on COVID-19 vaccines made by Moderna, Pfizer, and Johnson & Johnson doesn’t “prohibit public or private entities from imposing vaccine requirements, even when the only vaccines available are those authorized under EUAs.”