Statement made yesterday by a Senator to Zuckerberg.
Obviously violence is not possible through the platform itself, though statements about violence are possible. So this meant statements about violence.
The Senate is in consensus thus that Facebook should not allow its users to talk about BLM and the possibility police are using extreme levels of violent force.
Likewise FB should not be allowed to talk about US foreign policy as pertains to wars, bombings, drones, etc.
Discussing these topics is not part of Free Speech, according to all US Senators, and agreed upon by Zuckerberg.