The US Department of Labor implemented a new rule Monday that allows federal contractors to discriminate against employees under the guise of religious freedom. This ruling could affect more than four million employees.

The rule expands the definition of religious organizations to include for-profit organizations as well as traditional religious charities and churches. It also allows employers to subjectively define what types of discrimination fit within the religious tenets they ascribe to.

The American Civil Liberties Union (ACLU) provides an example of how this rule expands a company’s ability to discriminate against employees for a wide scope of behaviors:

This definition expands the permitted discrimination beyond, for example, a Jewish social services organization being allowed to require that its program director be Jewish, to the organization being permitted to fire any employee, including one not of the faith, who does not follow all the tenets of the organization’s faith.

The rule contradicts the language of the order it claims to clarify, which prohibits religious organizations from discriminating against employees for belonging to protected categories such as sex or race. The ACLU says, “As long as discrimination can be cast as ‘adherence to religious tenets,’ an employer could claim a license to discriminate under the Proposed Rule.”

Secretary of Labor Eugene Scalia approved this regulation within the last month-and-a-half of his tenure in the department. Critics predict that President-elect Joe Biden administration will roll back the rule but say it could take years to get through administrative red tape.