Though in this particular case, they were breaking criminal law in the course of intervening in a civil dispute. They were attempting to simultaneously act as police and as private security personnel for the airline.

One cannot serve two masters. You cannot serve the public interest as police and a private interest as a security thug at the same time.

Following orders takes no guts. It takes guts to refuse to obey an unlawful order. The Nuremberg Principle still exists.