(Reuters) - A federal judge has overturned a jury verdict convicting a onetime business partner of former U.S. national security adviser Michael Flynn of illegally lobbying for Turkey.

FILE PHOTO: Former U.S. national security adviser Michael Flynn seen in a file photo after his sentencing was delayed at U.S. District Court in Washington, U.S., December 18, 2018. REUTERS/Joshua Roberts/File Photo

U.S. District Judge Anthony Trenga ruled that prosecutors failed to show that Bijan Rafiekian knowingly acted as a secret agent for Turkey’s government under Ankara’s direction or control, and concealed his role from U.S. authorities.

“The verdict was against the heavy weight of the evidence,” the judge wrote in a 39-page decision on Tuesday.

A spokesman for U.S. Attorney G. Zachary Terwilliger in Alexandria, Virginia, said that office was reviewing the decision.

Rafiekian, co-founder of the Flynn Intel Group consulting firm, had been convicted on July 23 after a weeklong trial.

“Bijan and his family are relieved and looking forward to getting on with their lives,” his lawyer Mark MacDougall said. “Justice has been done.”

Trenga’s decision marked the latest setback in the U.S. Department of Justice’s efforts to thwart unauthorized lobbying for foreign governments by enforcing such laws as the federal Foreign Agents Registration Act (FARA).

Earlier this week, federal prosecutors in Manhattan closed a FARA-related probe into Tony Podesta, brother of former White House adviser John Podesta, and former Congressman Vin Weber without filing criminal charges, representatives for both men told Reuters.

The investigation grew out of Special Counsel Robert Mueller’s probe into Russian interference in the 2016 election and was focused on lobbying work for Ukraine directed by Paul Manafort, President Donald Trump’s former campaign chairman.

“I have been notified that the investigation relating to Vin Weber is over,” Weber’s lawyer Robert Trout said in a statement. “At all times Mr. Weber acted in good faith and in keeping with the legal advice his company received from its outside counsel.”

On Sept. 4, another jury acquitted Greg Craig, who was White House counsel under former President Barack Obama, of lying about his work for Ukraine.

That case also arose from Mueller’s probe.

The Justice Department has ramped up FARA enforcement since 2015, after bringing just seven criminal cases under that law in the prior half-century.

Rafiekian was accused of conspiring with Turkish-Dutch businessman Ekim Alptekin to lobby on Turkey’s behalf to persuade the U.S. government to extradite dissident cleric Fethullah Gulen.

Turkey has accused Gulen of orchestrating a failed 2016 coup to topple President Tayyip Erdogan. Gulen, who lives in self-imposed exile in a fortified Pennsylvania compound, has denied any involvement.

Alptekin remained abroad during Rafiekian’s trial and has denied the allegations against him.

It was unclear how Trenga’s decision would affect the criminal case against Flynn, who lasted three weeks as Trump’s first national security adviser.

Flynn faces a scheduled Dec. 18 sentencing, after having pleaded guilty to lying about his conversations in December 2016 with Russian’s ambassador to the United States about sanctions that Obama had imposed on Moscow.

Prosecutors called off plans to have Flynn testify against Rafiekian, deciding instead to portray the retired U.S. Army lieutenant general as Rafiekian’s co-conspirator.

A lawyer for Flynn did not immediately respond to requests for comment.

Trenga said if a federal appeals court found enough evidence to sustain Rafiekian’s conviction, he would grant a new trial, citing concern about his own jury instructions.

The case is U.S. v Rafiekian, U.S. District Court, Eastern District of Virginia, No. 18-cr-00457.