insulted by manager

she called us ***** saying we didn't arrive on time and threatened to lay charges against us because we were frustrated and projecting our voices. how can you speak soft whole someone is insulting u in public? the police checked surveillance and saw that we were actually on time but she refused to apologize instead she was more interested in teaching us "manners" while her staff was cheering on while she was insulting us and after that threatened us telling us she will make sure we don't take a flight British airways again as if we are going to take the flight for free! I will make sure I warn my family and friends and colleagues about this pathetic airline!