A group of parents is suing attorney general Merrick Garland for criminalizing free speech.
Earlier this month Garland asked the FBI to investigate the recent rise in threats against school board members and school personnel.
Garland's memo also noted the people making those threats could be prosecuted.
But the American Freedom Law Center – a conservative law firm – is filing a lawsuit on behalf of parents from Michigan and Virginia.
According to the suit, those parents believe their school districts are spreading "harmful, immoral and racist policies of the progressive left."