Washington — A federal judge on Monday invalidated President Trump’s policy imposing a $100,000 fee on new H-1B visas for high-skilled foreign workers, finding it unlawful.

U.S. District Judge Leo Sorokin ruled in favor of a group of 20 states that challenged the new fee announced by Mr. Trump in September. The judge found that the Trump administration overstepped its authority by imposing a $100,000 tax on H-1B applications without authorization from Congress. 

“The substance and application of the $100,000 payment reveal that it is a tax, regardless of what the payment is called,” Sorokin wrote in a 42-page decision.

The judge, appointed by former President Barack Obama, wrote that “there are no statutory powers authorizing [the Trump administration] to implement a $100,000 tax on H-1B petitions.”

The H-1B visa program was created by Congress in 1990 and allows U.S.-based companies to temporarily hire foreign workers in a specialty occupation for up to six years. Congress capped the number of H-1B visas at 65,000 per year. Another 20,000 of the visas can be issued for people with advanced degrees. Under the program, employers are also required to pay certain fees, typically ranging between $1,700 to $4,500.

But last year, Mr. Trump signed a proclamation that added a $100,000 payment to all new H-1B applications. The president argued the H-1B visa program “has been deliberately exploited to replace, rather than supplement, American workers with lower-paid, lower-skilled labor,” which he said had “undermined both our economic and national security.”

The Trump administration moved swiftly to implement his proclamation. U.S. Citizenship and Immigration Services said in October the $100,000 fee applied to new applications filed on or after Sept. 21, just two days after Mr. Trump announced the new policy. The agency clarified that the fee would only apply to new applicants living abroad, and not renewals.

The coalition of states, led by California, filed their lawsuit challenging the fee in December and alleged that the new policy was unlawful. The states warned that the $100,000 fee would hamper their ability to hire high-skilled workers in several areas, including at primary and secondary schools, in public colleges and universities, and at medical facilities.

In his decision, Sorokin found that Mr. Trump had no power or authorization from Congress to impose a tax on H-1B applications. He said the record in the case lacked any indication that the Trump administration “reasonably explained” the decision to implement the $100,000 fee, and found that none of the policy rationales from federal agencies “offer a reasonable explanation for enacting a heavy tax on the H-1B program.” 

He ordered the required visa payment to be set aside in its entirety, relief that is allowed under a federal law called the Administrative Procedure Act.