STORY: The criminal case accusing Donald Trump of illegally holding onto classified documents was dismissed Monday.

Judge Aileen Cannon of Florida, who was appointed to the bench by Trump, ruled that Special Counsel Jack Smith, who is leading the prosecution, was unlawfully appointed.

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In June of last year, Smith announced charges against Trump saying that he willfully retained sensitive national security documents at his Mar-a-Lago estate after leaving office in 2021 and obstructed government efforts to retrieve the material.

But Cannon found that U.S. Attorney General Merrick Garland did not have the authority to appoint Smith to the role of special counsel, and that Smith did not have the authority to bring the case.

Prosecutors are likely to appeal the ruling, and courts in other cases have upheld the ability of the Justice Department to appoint special counsels to handle certain politically sensitive investigations.

Still, the dismissal marks another major legal victory for Trump, who is set to be formally named the Republican presidential nominee in Milwaukee this week.

Earlier this month, the U.S. Supreme Court ruled that Trump enjoyed immunity from prosecution for many of his actions in office.

That ruling involved charges pursued by Smith in a separate case against Trump involving his efforts to overturn his 2020 election loss.

Trump, who also just survived an assassination attempt, said in a social media post that Monday's ruling should be a "just the first step" and called for the dismissal of all four criminal cases against him.