ride roughshod over (someone or something) To treat someone or something with marked disdain, brutality, or contempt; to act without regard for the well-being of something or someone.

Act without regard for the feelings or interests of others, as in She just forges on, riding roughshod over her colleagues. This term alludes to the practice of arming horses with horseshoes mounted with projecting nails or points, which both gave them better traction and served as a weapon against fallen enemy soldiers.