Former FBI Director James Comey asked a federal judge to dismiss charges accusing him of threatening President Trump, arguing the case violates his First Amendment rights.

The charges stem from an Instagram post showing seashells arranged to form “86 47,” which prosecutors say could be interpreted as a threat, while Comey’s lawyers argue it was political expression.

Comey’s defense team said the phrase “86” commonly means to remove or reject someone and does not imply violence.

They argued that prosecuting him for the post could unfairly punish political speech and set a dangerous precedent, CBS News has reported.

Comey, who has pleaded not guilty, is expected to continue seeking dismissal of the charges before his September arraignment.