The Supreme Court on Tuesday questioned whether federal prosecutors went too far in bringing obstruction charges against hundreds of participants in the Jan. 6, 2021, Capitol riot. But it wasn’t clear how the justices would rule in a case that also could affect the prosecution of former President Donald Trump, who faces the same charge for his efforts to overturn his election loss in 2020.

The justices heard arguments over the charge of obstruction of an official proceeding in the case of Joseph Fischer, a former Pennsylvania police officer who has been indicted for his role in disrupting Congress’ certification of Joe Biden’s 2020 presidential election victory over Trump. Fischer is one of 330 people facing that charge, which stems from a law passed in the aftermath of the Enron financial scandal more than two decades ago to deal with the destruction of documents.

Trump is facing two charges in a separate case brought by special counsel Jack Smith in Washington that could be knocked out with a favorable ruling from the nation’s highest court. Next week, the justices will hear arguments over whether the former president and presumptive nominee for the 2024 Republican nomination has “absolute immunity” from prosecution in that case, a proposition that has so far been rejected by two lower courts.

Smith has argued separately in the immunity case that the obstruction charges against Trump are valid no matter how the court decides Fischer’s case. The first former U.S. president under indictment, Trump is on trial on hush money charges in New York and also has been charged with election interference in Georgia and with mishandling classified documents in Florida.

It was not clear after more than 90 minutes of arguments precisely where the court would land in Fischer’s case. Conservative justices Samuel Alito and Neil Gorsuch appeared most likely to side with Fischer, while liberal Justices Elena Kagan and Sonia Sotomayor seemed more favorable to the Justice Department’s position.

Justices Amy Coney Barrett and Ketanji Brown Jackson, a former federal public defender, expressed interest in more of a middle-ground outcome that might make it harder, but not impossible, for prosecutors to use the obstruction charge.

Some of the conservative justices said the law was so broad that it could be used against even peaceful protests and also questioned why the Justice Department has not brought charges under the provision in other violent protests.