Prosecutors from special counsel Robert Mueller’s office wrote in court documents filed Friday that former national security adviser Michael Flynn’s false statements to the FBI were “voluntary and intentional,” NBC News reports. In the memo, the prosecutors said there was “no basis” for Flynn’s assertion that he had been coerced into lying to the FBI in a January 2017 conversation. “The interview was voluntary, and lacked any indicia of coercion,” the documents said. “A sitting National Security Advisor, former head of an intelligence agency, retired lieutenant general, and 33-year veteran of the armed forces knows he should not lie to federal agents.” Flynn pleaded guilty last year to making false statements to the FBI when asked about his interactions with Russian ambassador Sergey Kislyak before President Trump took office. While rejecting Flynn’s claim that he was coerced into lying because he “saw the FBI agents as allies,” Mueller’s office still recommended that he receive little to no jail time due to his assistance with their probe into Russian interference in the 2016 election. Flynn faces up to six months in prison, and he is slated for sentencing on Dec. 18.