Originally Posted by bocastephen

Fair enough - but as mentioned, an inop lavatory is placarded as such, so that is really a different situation than described. If the lavatory is placarded inop, I’m certainly not going to just use it and risk creating a mess, but I might ask if I’m having an emergency and see it used by crew.

Having said that, that’s not really what the OP claimed - blocking the lavatory “for security” is not in the MEL, FAA regulations, or unless you have content to the contrary, in the United procedures manual. It’s a case of selective choice by a crew member who almost certainly wanted to reserve a private restroom for themselves to the detriment of paying customers.

Unfortunately given the often hostile relationship between employees and customers, we really have no other option but to assume unprofessional conduct by the pilot of that flight.