US President Donald Trump granted a pardon on Friday to a former New York police sergeant who was convicted of helping China try to scare an ex-official into going back to his homeland, a prominent case in US authorities’ efforts to combat what they claim are Beijing’s far-flung efforts to repress critics.

Michael McMahon was sentenced this spring to 18 months in prison for his involvement in what a federal judge called “a campaign of transnational repression”.

He insisted he was innocent, saying he was “unwittingly used” when he took what he thought was a straightforward private investigator gig. McMahon said he was told he was working for a Chinese construction company, not the nation’s government.

A White House official, speaking on Friday on condition of anonymity to discuss a pardon that has not been publicly announced, pointed to McMahon’s explanation that he had been misled.

The official also noted that McMahon earned dozens of commendations before a 2001 injury ended his 14-year NYPD career.

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Trial begins for 3 suspected Chinese agents accused of harassing US-based fugitive

Trial begins for 3 suspected Chinese agents accused of harassing US-based fugitive

McMahon’s lawyer, Lawrence Lustberg, said the pardon “corrects a horrible injustice”.