U.S. District Judge Emmet Sullivan on Tuesday dismissed a criminal case against former Trump administration national security adviser Michael Flynn.

However, the federal judge noted that the pardon Flynn received from President Donald Trump last month does not guarantee his innocence, as reported by the Associated Press.

Sullivan's order was expected because of Trump's presidential pardon. 

In his 43-page order, Sullivan noted that the president's broad pardon powers required dismissal, but emphasized that the pardon did not mean that Flynn is innocent of a crime that he had twice pleaded guilty to committing. 

Related story: Trump Pardons Former Security Adviser Michael Flynn Despite Guilty Plea for Lying to FBI

A request from the Justice Department to drop the case was still pending when Flynn's pardon was issued.

In dropping the case in U.S. District Court in Washington, D.C., Sullivan cited the president's own interest in the case, adding that the pardon is "a political decision, not a legal one."

"Because the law recognizes the President's political power to pardon, the appropriate course is to dismiss this case as moot," Sullivan added.

The judge also said that the scope of the pardon is extraordinarily broad, according to a CNBC report. He noted that it does not only apply to the false statement offense, which Flynn twice pleaded guilty to.

Sullivan added that it also applies to any possible offenses that he might be charged with in the future concerning the case and "Special Counsel (Robert) Mueller's investigation."

Justice Department spokeswoman Kerri Kupec said the dismissal of the case is the correct result.

Meanwhile, Trump congratulated Flynn on the judge's decision through a tweet. He tweeted that Flynn and his family "have suffered greatly."

Sullivan rejected the Justice Department's request for months. The dismissal of the case brings an end to the yearlong issue, which involves Flynn.

Flynn was ousted from his White House position just weeks into his tenure.

Flynn Pleading Guilty

The former national security adviser twice admitted guilt during Mueller's Russia investigation. 

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Flynn admitted guilty to lying to the Federal Bureau of Investigation (FBI) about the talks he had during the presidential transition period with the former Russian ambassador to the United States. 

The conversation included sanctions that the Obama administration had just implemented on Russia for election interference. However, despite Flynn pleading guilty, the Justice Department last spring hurriedly moved to dismiss the case.

The department argued that there was an insufficient basis for the FBI to have questioned him in the first place. The Justice Department also argued that Flynn's statements made during the interview were immaterial to the investigation.

Flynn cooperated with Mueller's probe into Russian meddling in the election. He was also questioned whether the Trump campaign had coordinated with the Russians.

Sen. Richard Blumenthal said in late November that Trump's pardon of Flynn "is as rotten as it is unsurprising." Blumenthal is a Democratic member of the Senate Judiciary Committee.