A federal judge ruled Tuesday transgender people will not face criminal charges if they use an Idaho public restroom that does not match their gender identity.

The Idaho law, adopted in March and signed into law by Gov. Brad Little, was set to take effect Wednesday, July 1.

"No one should be forced to choose between the threat of arrest for being themselves in public or the threat of harassment and violence for acting the way the state wants them to be," American Civil Liberties Union lawyer Barbara Schwabauer said in a statement.

"The preliminary injunction is a vital first step as we continue to challenge this gross violation of privacy and fundamental equality until the law is blocked for good," Schwabauer added.

Six transgender Idaho residents were represented by the ACLU and Lambda Legal.

While 19 states have bathroom laws, Idaho’s law applied to restrooms in private buildings, as long as they are open to the public.

Violators could face up to a year in jail for a first offense and up to five years in prison for a second offense.

The law included exceptions allowing a person to use a single-use restroom designated for the "opposite sex" if it’s the only "reasonably available" one, and if the person is in "dire need" of using the restroom.

The state had previously enacted laws that requited people to use bathrooms matching their sex at birth in primary schools and in colleges.

The Idaho Chiefs of Police Associations said it was concerned about how police would determine if someone was in "dire need."

Judge Amanda Brailsford, a Biden appointee, mostly agreed with the plaintiffs the law was unconstitutionally vague

The law "imposes criminal penalties — up to a felony for repeat violations — yet leaves critical enforcement decisions to the unguided discretion of individual officers," Brailsford wrote in her ruling.

Brailsford ruled the law couldn’t be enforced against someone using a single-stall restroom or when no single-user restroom is available and unoccupied on the same floor as a multi-user facility.

But the law will still apply to locker rooms and showers.

Idaho Attorney General Raul Labrador said he plans to appeal.

"This is a results-driven decision that misapplies the law, confuses the issues, and misrepresents the position of the State," Labrador said in a statement.

"Biological sex is not vague, and neither is this law," he said.

Associated Press contributed to this report.