Why were mirrors used as a form of protest to the Dakota Access Pipeline? as more of a symbolic gesture than physical battle regalia
in reference to the need for protection after police used water canons
to encourage reflection by the supporters of the pipeline itself
to call attention to the role artists can play in controversial situations
all of the other answers

The signs aren't designed to set fires, but to reflect an image of police and to distract them with flashing light. “There is a two-fold effect of having police be reflected into the mirrors,” says designer Nikolas Bentel. “First, the mirrors will be a way for the police to see who they have become.

Explanation:

hope this help

answeras live actors preforming in the same room as a live audience;