Numbers being overblown? The protests from the left which have dominated the public consciousness have been motivated around the idea that unarmed black people

Numbers being overblown? The protests from the left which have dominated the public consciousness have been motivated around the idea that unarmed black people are being killed en masse by the police, a fate literally less likely to happen than a person being struck by lightning. Please explain to me how you determine what exactly constitutes numbers being overblown for propaganda purposes.