In a case that could have a major impact on the over 350 people found guilty of illegally entering the U.S. Capitol on Jan. 6, 2021, the Supreme Court was hearing arguments Tuesday that could place those convictions in jeopardy.

Former Pennsylvania police officer Joseph Fischer brought his case before the high court seeking relief on an obstruction charge -- one of seven counts he was convicted of for his involvement in the Jan. 6 riots. If his appeal is granted, other convictions could be overturned on the same legal grounds.

Fischer's lawyers claim that their client arrived at the Capitol after Congress had already adjourned, absolving him of a role in obstructing the business of the governing body. Fischer claims he spent only four minutes inside the Capitol and advanced only 25 feet before leaving without incident.

However, prosecutors claim Fischer even informed his police chief that he might resort to violence on the day of protest in favor of then-President Donald Trump. Video evidence captures Fischer shouting "Charge!" before entering the Capitol and making other violent statements.

The case could have a dramatic impact on the federal convictions, many of which used the obstruction charge against the pro-Trump defendants. However, the majority of those convicted were also found guilty of more serious felony charges.