Mike Irving, the Reddit user who posted the video, shed a little light on the situation:
She came on the plane yelling and swearing about how we are going to Portugal and not Brazil. She continued being loud and obnoxious and I’m assuming that some of the families with younger children told the flight attendants, who then called the police. When the police came, she refused to move, started screaming at them and telling them she would sue, and when they told her she would be arrested if she didn’t cooperate that just edged her on more. Eventually that man (not sure if he was a cop or not) basically said f*** it you’re being carried off this plane.