J.Law shared photos of marchers with her 16,516,090 fans and is calling on them to see if they recognize any familiar faces.
"These are the faces of hate," she writes. "Look closely and post anyone you find. You can't hide with the internet you pathetic cowards!"
The post inspired a heated constitutional law discussion on the legality of this vigilante missions to name white supremacists.
Some of her fans appear to be fascist sympathizers, perhaps viewing The Hunger Games as a cool society to live in.
And some actually defied the odds and learned something from replies to Facebook comments.
Whether you agree with the vigilante tactics or not, it's nice to see someone with a huge fan base unequivocally condemn white supremacists (ahem, Mr. President).