WASHINGTON — An unidentified foreign government is asking the Supreme Court to get involved in a case that may be part of special counsel Robert Mueller’s Russia investigation.

The justices on Tuesday granted the government’s request to file a censored version of an appeal to the high court in which the country is fighting a grand jury subpoena and a $50,000-a-day fine for not complying with the subpoena.

The appeal doesn’t identify the country, a company it controls or even the lawyers who are representing it. But the appeal says the justices should make clear that a federal law that generally protects foreign governments from civil lawsuits in the U.S. also shields them in criminal cases.

The justices had previously refused to block the subpoena and fine on an emergency basis.

A three-judge panel of the federal appeals court in Washington had in December upheld the issuance of the subpoena and a contempt order issued by a district court judge when the company, identified only as wholly owned by a foreign country, failed to comply.

The country says that the appellate ruling would upset foreign relations in a big way if allowed to stand. It says the U.S. Circuit Court of Appeals for the District of Columbia is “the first appellate court in American history to exercise criminal jurisdiction over a foreign state.”

The country says it is immune from being subpoenaed under the Foreign Sovereign Immunities Act and that complying would require it to violate its own laws.